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1 Online access information sources and services Introduction.

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1 1 Online access information sources and services Introduction

2 2 Online information sources: summary The following gives a general overview of online accessible information sources. This overview is not limited to or focusing on a particular concrete subject domain/area.

3 3 Online information sources: prerequisites Before using online accessible information sources, you should ideally have some knowledge and skills related to computer hardware computer software the Internet the WWW the concept of information information retrieval in general the information market

4 4 Discovering online access information sources Equipment and tools required: »A microcomputer »Data communication facilities »Tools to locate information sources »Some knowledge and skills »...

5 5 Growing importance of computer network information resources Networked information resources are growing at a high rate, not only in volume but also in importance. There are many sources there which are vital to research and many others which are useful generally. To keep abreast of their field, most academics and researchers will find an increasing need to use the network for fast and efficient communication and for access to information. If they dont, they are likely to be left behind, because most of their colleagues in institutions around the world will be doing just that.

6 6 Online access to information: avoid network traffic jams To access from Europe online information sources in the US, work when lines are not saturated. (better in the morning than in the afternoon)

7 7 Internet based information sources: problems / difficulties (Part 1) Redundancy and overlap: On the one hand, there is too much information on some topics; in other words, the redundancy and overlap are high in many cases. Too few information sources: On the other hand, there are too few information sources on some topics.

8 8 Internet based information sources: problems / difficulties (Part 2) No order is imposed on most sources. Quality checks / quality controls are not performed. Related to this: it is not required to register new information offered. Is the information that you find real, honest, authentic?

9 9 Internet based information sources: problems / difficulties (Part 3) Change is the only constant: Information sources are constantly changing, growing, but sometimes disappearing.

10 10 Internet based information sources: problems / difficulties (Part 4) Scattering: There is no single simple but powerful system to find relevant information through the Internet. In other words: integration / aggregation is still far from perfect.

11 11 Internet based information sources: problems / difficulties (Part 5) Slow: The Internet is in many places and for many applications not yet fast enough.

12 12 Internet based information sources: problems / difficulties (Part 6) In conclusion: Surfing, using the Internet, the WWW, can be a time sink instead of a productive activity.

13 13 Internet based information sources: how many? how much information? In 2001: More than million unique URLs in the total Internet More than 10 terabyte (= gigabyte) of text data

14 14 Increasing number of online public access databases Source: Gale Directory of Databases, 1997.

15 15 Online access information sources and services Types of online access information systems

16 16 Types of online access information systems We can categorize the various online accessible information systems in various ways: »primary or secondary »based on information contents that is offered »online access method required (= communication protocol) »freely accessible versus accessible for a fee »computer file format (Of course these categorizations are normally not independent but related.)

17 17 Primary versus secondary computer sources / systems / services Primary sources /systems /services directly useful Secondary sources /systems /services »helping to access / use the primary services »travel agencies, navigation services,...

18 18 !? Question !? Task !? Problem !? Do you know examples of primary and of secondary online information systems?

19 19 Types of online access information systems by contents Documents (with or without hyperlinks) Catalogues of editors and bookshops Online public access library catalogues (OPACs) Community/Campus-Wide Information Systems (CWIS) Online access databases about journal articles Electronic newsletters and journals Computer file archives (documents, programs) Interest groups (for instance Usenet Newsgroups)...

20 20 Types of online access information systems by access method Remote login information systems and bulletin board systems (BBS) (telnet in the Internet) Anonymous ftp servers, in the Internet Usenet News servers (nntp in the Internet) Gopher servers, in the Internet Wide Area Information Servers (WAIS), in the Internet World Wide Web servers = http servers (WWW), in the Internet...

21 21 Types of online access information systems: free versus fee A lot of the information on the Internet is available free of charge, but another part is only accessible when a fee is paid to the producer and / or the distributor. Some organisations pay these fees for some sources and then organise access, so that the members of the organisation can retrieve and exploit the information as if it is free of charge.

22 22 Types of online access information systems: free versus fee Public access information sources free of charge Fee-based online information services (NOT free of charge)

23 23 Types of online access information systems: free for members only Public access information sources free of charge Fee-based online information services (NOT free of charge) Fee-based online information services, made accessible free of charge by an institute to its members

24 24 Types of online access information sources by file format For instance: »TXT (ASCII) »DOC »HTM, HTML, SHTML,… »PDF »PCX »TIF, TIFF »GIF »JPG »PNG »AVI »MPG »ASF »…

25 25 WWW sites classified by contents Commercial: about 80% Other 20%: »Science and education »Personal »others in 1999 (according to Lawrence and Lee Giles, Nature, 1999, Vol. 400, pp )

26 26 Commercial information provided through the Internet Most of the information that is freely available on the WWW is provided by commercially oriented organisations. Thus that information is not objective or scientific in most cases, but subjective or perhaps even misleading, and certainly attracting more attention than more scientific information. (Of course many information sources are also provided by commercial organisations that belong to the so-called information industry, but these are bound to supply more objective information of high quality, as this is their way to survive commercially.)

27 27 WWW sites classified by language English: about 87% Other languages: 13% in 1999

28 28 Online access information sources and services Internet-based encyclopedias

29 29 Encyclopedias accessible through Internet and WWW Dictionaries and encyclopedias are the first choice among many types of information sources, »when we do not need detailed information on a common topic »when we want to prepare a more detailed search on an unfamiliar topic, by searching for the right spelling, synonyms, context,… Some dictionaries and encyclopedias are available through the WWW free of charge.

30 30 Encyclopedias accessible through Internet and WWW: examples Encarta Concise Free Encyclopedia »http://encarta.msn.com/http://encarta.msn.com/ Encyclopædia Britannica only a small part is available free of charge + links to selected WWW sites »http://www.britannica.com/http://www.britannica.com/ Encyclopædia Britannica Concise »http://education.yahoo.com/reference/encyclopedia/http://education.yahoo.com/reference/encyclopedia/ Example

31 31 Encyclopedias accessible through Internet and WWW: examples The Canadian Encyclopedia (in English and in French): »http://thecanadianencyclopedia.com/http://thecanadianencyclopedia.com/ Example

32 32 Encyclopedias accessible through Internet and WWW: overviews A list / overview of encyclopedia on the Internet: Other lists of encyclopedia on Internet can be found as a part of more general directories of Internet-based information sources. Example

33 33 Online access information sources and services Internet search functions built in browser software

34 34 The Internet search functions built into browsers Some Internet search functions are built into common leading browsers like »Microsoft Internet Explorer »Netscape When connected to the Internet, you can use »The functions behind the Search button »Searching through the Address form

35 35 The Internet search button of browsers: introduction Common graphical browsers provide a search function and a search button. Examples: Netscape, Microsoft Internet Explorer

36 36 The Internet search button of browsers: comments (Part 1) Such a search function offers in fact no searching, but (only) a link to a WWW site, often in the USA, which offers links or gateways to search tools on other servers. It is faster in many cases to contact search tools directly.

37 37 The Internet search button of browsers: comments (Part 2) The gateways may offer only a limited view on the properties of the real search tool used. Such a search function can confuse users who may think that the searching capability is built more or less into the browser software, while searching relies on external servers.

38 38 Searching with browsers using the address form: introduction A search for particular Internet documents can be performed by typing in keywords in the address form, when you are connected to the Internet, for instance with »Microsoft Internet Explorer »Netscape This is based on transmitting the keywords to some Internet index through the Internet.

39 39 !? Question !? Task !? Problem !? Get some experience in using the address form of your web browser program to search for documents on a particular subject that are available on the WWW.

40 40 Searching with browsers using the address form: comments + An advantage is the ease of use. - A disadvantage is that it less clear what really happens, than when you access a well chosen and well known Internet directory or Internet index directly.

41 41 Online access information sources and services Internet directories and indexes

42 42 Internet: meta-information about Internet information sources in printed manuals and guides: - it is not always possible to get a copy fast - it costs money to get a copy - they are soon out of date offered on the WWW!: + directly available when we want to use the Internet + many systems are accessible free of charge + most systems are regularly updated (intelligent agent software on client PC)

43 43 Internet: subject-oriented meta- information offered via WWW Information about information sources: in the form of »subject guides = texts with references »subject hypertext directories = subject guides »key word indexes, generated automatically, for searching »collections of links or forms to the above »(multi-threaded search systems)

44 44 Internet global subject directories: introduction They are virtual libraries with open shelves, for browsing. They are manually generated, man-made by many people. They can be browsed following a tree structure or a more complicated variation. The most famous of these systems belong to the most popular and most visited sites on the WWW: e.g. Yahoo!

45 45 Internet global subject directories: structure The structure corresponds to a classification that is in most cases specific for the particular overview. In other words: the well-known and classical universal classification systems are not used in most Internet directories.

46 46 Internet global subject directories: limitations They cover only a small number of selected WWW sites, in comparison with the total number of sites that are accessible. They are suitable mainly for broad searches that can be difficult to formulate in words, but NOT for more specific searches that require combinations of several concepts.

47 47 Internet global subject directories: searching directories with a query Many of the Internet directories include an index to search their contents with a query. However, then the assisting classification structure is not well exploited and the user should be aware of the problems and difficulties of information retrieval with natural language queries. Furthermore, the possibility to use the system in this way may be confusing, as these directories are not real full- text Internet indexes, like those provided by other search tools.

48 48 Internet global subject directories: Yahoo! A hypertext global subject directory can be found at and at many other sites, including Entries are NOT rated. Accessible free of charge. Example

49 49 Internet global subject directories: searching with a query in Yahoo! (1) The directory of Yahoo! can not only be browsed, but can also be searched with a query. However, in this way the hierarchical structure is not well exploited. For the formulation of a search query, Yahoo! can provide automatic assistance related to spelling and word variations. For instance: After searching for Capetown, Yahoo! Answers: Other Spellings: Try searching for cape town instead.cape town Example

50 50 Internet global subject directories: searching with a query in Yahoo! (2) When such a query does not provide results, then Yahoo! uses a much larger external Internet index (not produced by Yahoo!) to execute a query based on textual search statements. The chosen Internet index has varied over time. This mechanism is not made very clear and may confuse the user. Example

51 51 Internet global subject directories: Britannica A hypertext global subject directory can be found at Entries are rated. Accessible free of charge. Combined and integrated with a great encyclopedia. Example

52 52 Internet global subject directories: BUBL link A hypertext global subject directory to more than WWW sites for the higher education community can be found at Accessible free of charge. Example

53 53 Internet global subject directories: BUBL for marine biology Example

54 54 Internet global subject directories: Google directory A hypertext global subject directory can be found at Accessible free of charge. Very similar to the Open Directory Project. Example

55 55 Internet global subject directories: Librarians' Index to the Internet A hypertext global subject directory can be found at Accessible free of charge. Example

56 56 Internet global subject directories: LookSmart A hypertext global subject directory can be found at Links are offered to LookSmart by the Internet index AltaVista. A search in the LookSmart index is also executed with the Internet index AltaVista. Accessible free of charge. Example

57 57 Internet global subject directories: Magellan A hypertext global subject directory can be found at Accessible free of charge. Example

58 58 Internet global subject directories: Open Directory Project A hypertext global subject directory can be found at Accessible free of charge. Example

59 59 Internet global subject directories: Point (Communications) A hypertext global subject directory can be found at Accessible free of charge. Example

60 60 Internet global subject directories: Resource Discovery Network A collection of hypertext subject directories that focus on academic information sources can be found at Together these lead to more than selected WWW sites. Accessible free of charge. Example

61 61 Internet global subject directories: lists of directories Many Internet global subject directories exist, but the ideal one is not available. Overviews / lists of Internet subject directories exist also. Examples (accessible free of charge): »http://www.surfnet.nl/http://www.surfnet.nl/ »http://searchengineshowdown.com/dir/http://searchengineshowdown.com/dir/

62 62 Internet global subject directories: using more than one at the same time A system allows you to use several European Internet subject directories at the same time. This is available free of charge through

63 63 !? Question !? Task !? Problem !? Try to find Internet sources which are relevant for you, by using an Internet-based global subject directory.

64 64 Internet global subject directories: evaluation criteria (Part 1) Is usage free of charge? Wide coverage? Up to date? Frequent updates? Only few dead / broken links? Good coverage of the sources in that part of the world in which you are interested? Does the manager of the directory refuse to give priority to sites that want to pay to get a prominent place in the directory?

65 65 Internet global subject directories: evaluation criteria (Part 2) Easy user interface? Short response times? Are mirror sites available closer to you for faster response? Good presentation, description of each site? Is a rating, appreciation, review offered for each listed site? Is translation of documents offered free of charge?

66 66 Internet global subject directories: evaluation criteria (Part 3) Good documentation and online help? Good help desk available? High stability and reliability?

67 67 Internet global subject directories: evaluation criteria (Part 4) Are other services offered from the same site or with the same interface? Is the subject directory integrated with other services? Additional services can be »an Internet index or a WWW index or a gateway to such an index for searching with a query »travel guides, flight and hotel reservations, maps,... »WWW-based and address directories »auctions through WWW

68 68 Internet subject directories: non-global, more specific systems a directory limited to sources in/of a country or region a directory restricted to a specific subject domain (portal) a global subject directory the complete WWW can lead to

69 69 Internet subject directories focusing on a specific subject domain (Part 1) Computer science & engineering: Social sciences: Marine science and oceanography: Examples

70 70 Internet subject directories focusing on a specific subject domain (Part 2) Medicine and healthcare: general: Medicine and healthcare: General pediatrics: Examples

71 71 Internet subject directories focusing on a specific subject domain (Part 3) Engineering: Civil engineering: Fishing: Art, architecture and the media: or Examples

72 72 Internet indexes: automated search tools Several systems allow to search for and to locate many items (addressable resources) in the Internet in a more systematic, direct way than by only browsing/navigating. These systems do NOT search the contents of computers through the real Internet in real time and completely when a user makes a query. Searching in that way would be much too slow due to limitations in the technology.

73 73 Internet indexes: scheme of the mechanism User searching for Internet based information Internet client hardware and software user interface to a search engine Internet information source Internet index search engine Internet crawler and indexing system database of Internet files, including an index

74 74 Internet indexes: description of the mechanism Each of these search systems is based on: a database of links to pages / URLs that can be retrieved by searching with queries through a big index that is built machine-made on the basis of the contents, the texts, of these pages (to build this database and to keep it up to date, pages are continuously collected from the Internet by a robot computer software system) a search system with a user interface in a WWW form, to allow the user to search through that database

75 75 Internet indexes: AltaVista Example The primary search interface can be found in the US: (These addresses all lead to the same information.) Mirror site in UK:

76 76 Internet indexes: AltaVista: features Allows full text searching of the WWW Allows advanced Boolean searching (in Advanced mode) Offers relevance ranking of search results Offers a link to an Internet subject directory (Looksmart) Offers links to systems to find images, sounds,… (multimedia) in the Internet Example

77 77 Internet indexes: AltaVista simple versus advanced Simple is suited for instance for searches »with only 1 concept expressed as a series of synonyms, narrower terms,... such as a search for a person, a company, an institute,... »when ranking is important Advanced is suited for instance for searches »with more than 1 concept so that an AND combination is useful, besides an OR combination »when ranking is not important Example

78 78 Internet indexes: Fast = All the Web Example The search interface can be found at: You can search the WWW and ftp servers. The database is one of the biggest.

79 79 Internet indexes: Google (Part 1) You can search for WWW pages at Does NOT offer/allow »full Boolean searches »manual or automatic stemming/truncation Example

80 80 Internet indexes: Google (Part 2) For retrieval an algorithm is used that takes into account the links between WWW pages. A retrieved page is ranked higher when »many sites/pages point to it »important sites/pages point to it Searches include full text searching of files on the WWW; not only html pages, but also files in the formats Adobe PDF, Microsoft Word, Microsoft Excel, Microsoft PowerPoint, Rich Text Format,… Example

81 81 Internet indexes: Google additional features Besides a system to search for WWW pages, Google offers also »a subject directory »searching for images on the WWW »searching an archive of Usenet messages + posting to Usenet groups Thus Google has become a great integrator / aggregator. Example

82 82 !? Question !? Task !? Problem !? Make a search with Google.

83 83 Internet indexes: Hotbot The search interface can be found at You can search the WWW Based on an Internet index created by Inktomi. Allows advanced, Boolean searching. Example

84 84 Internet indexes: Lycos The search interface can be found at Has been based on various databases of WWW pages over time. In : based on the Fast database of WWW pages, that forms also the basis for the search system Alltheweb. Example

85 85 Internet indexes: MSN Web Search The search interface can be found with the search functions build into Microsoft Internet Explorer and at Offered free of charge by Microsoft. You can search for Web content. Since Is based on an Internet index created by another company. Example

86 86 Internet indexes: coverage / size of each index The indexes grow and their size ranking is variable. Biggest systems in 2002: Google ! AltaVista (Fast =) All the Web (serving also Lycos) Systems based on the INKTOMI database of WWW pages, such as Hotbot, MSN Web search,…

87 87 !? Question !? Task !? Problem !? Try to find Internet sources which are relevant for you, by using an Internet index.

88 88 !? Question !? Task !? Problem !? Develop a suitable search query and apply this with an Internet search engine to find general reviews about monitoring seawater pollution Some advice: use synonyms, narrower terms, truncation, and Boolean combinations. Develop a suitable search query and apply this with an Internet search engine to find general reviews about monitoring seawater pollution Some advice: use synonyms, narrower terms, truncation, and Boolean combinations.

89 89 Internet indexes: delay in indexing new pages The great, well known, international Internet indexes have a delay of more than 1 month in indexing new pages. (according to Lawrence and Lee Giles, Nature, 1999, Vol. 400, pp ) So they are not suitable to search for rapidly changing recent information (such as news) (unless they index a small selection of important news sites more frequently.)

90 90 the complete WWW a global Internet index an index limited to sources in/of a country or region Internet indexes: non-global, regional systems

91 91 !? Question !? Task !? Problem !? Which Internet search system is closest to a classical library catalogue: an Internet subject directory or an Internet index? Which Internet search system is closest to a classical library catalogue: an Internet subject directory or an Internet index?

92 92 !? Question !? Task !? Problem !? Which differences do you see between a classical library catalogue and an Internet index?

93 93 Internet indexes: comparison with library catalogues Most Internet indexes have a larger database than most catalogues. Internet index databases do not correspond as well to the Internet as a normal, good catalogue corresponds to the collection, because the documents on the Internet change more often and their number is growing fast. Most Internet indexes contain all the words of the documents that they index, whereas catalogues only contain short descriptions of the documents.

94 94 Internet indexes: variations among various systems Besides their common aims and characteristics, we can nevertheless see differences, variations among the searchable Internet index systems. To illustrate these variations and to assist Internet users to make a decision on which search system to use, the following list of some features and evaluation criteria can be useful.

95 95 Internet indexes: evaluation criteria (Part 1) Is usage free of charge? How complete is the coverage? Is the coverage good (or poor) for a particular geographic region? Is the coverage good (or poor) for a particular type of documents? Is the searchable database up to date? Is the database updated frequently? Do the search results contain only few dead (broken) links?

96 96 Internet indexes: evaluation criteria (Part 2) Is spamming filtered out, to give other pages a better chance of turning up in the result set? Can the system cluster presumed duplicate documents in the results? Or does the system simply eliminate presumed duplicate documents from its database? Does the database system work with a full text indexing of each ASCII and HTML document that has a place in the database, so that full text searching is possible?

97 97 Internet indexes: evaluation criteria (Part 3) Are the contents of meta-fields also indexed to make them searchable? Does the system index also the text in files on the web that consist of non-ASCII codes to make these also searchable and retrievable? For instance files in the format of the various versions of »Microsoft Word »Microsoft PowerPoint »Adobe Acrobat (Portable Document Format)

98 98 Internet indexes: evaluation criteria (Part 4) Field indexing, so that searching for the contents of a particular field is possible? for instance: the HTML title,HTML keywords, URL, date, link,Java applet, text, image file, sound file,video file,...

99 99 Internet indexes: evaluation criteria (Part 5) Does the system offer powerful search options like »truncation? »word stemming? »Boolean search combinations? »proximity searching? »automatic translation of your search terms in several other languages? »spelling check of your search terms?

100 100 Internet indexes: evaluation criteria (Part 6) Can the results be limited to a certain time period? For instance based on the date »of the file as noted by the server computer, or »of the most recent indexing of the file Is the user interface easy to understand and efficient to use? Is a user interface offered in your own language? Does the system rank the items in the result set according to their presumed relevance?

101 101 Internet indexes: evaluation criteria (Part 7) Possibility to combine Boolean retrieval with relevance ranking of results? Can the results be ordered according to date »of the file as noted by the server computer, or »of the most recent indexing of the file Can the results be ordered according to size? Can all the results (documents) from the same site be grouped together?

102 102 Internet indexes: evaluation criteria (Part 8) Can the system rank the results (documents) on the basis of the number of WWW hyperlinks to that document? The system does not place/rank some results (documents) higher in the results list, on the basis of payments by the producer of those documents to the search system company.

103 103 Internet indexes: evaluation criteria (Part 9) Short response times? Are mirror sites available closer to you for faster response? Does the system offer a good presentation format of each result (document/page/item)? For instance: are search terms indicated / highlighted in the results? Good and detailed summary of each result available? Offers an analysis of words occurring in the results, which can help you to refine a search?

104 104 Internet indexes: evaluation criteria (Part 10) Is translation of documents offered free of charge? High stability and reliability? No large variations/fluctuations in the results from identical searches at different times. Good documentation and online help? Good help desk available? Can the search system provide updated results through electronic mail, as a current awareness tool?

105 105 Internet indexes: evaluation criteria (Part 11) Other services available besides the normal WWW index: »index to news resources, that is more frequently updated? »anonymous ftp file index? »gopher index? »searchable Usenet newsgroups archive? »Internet subject directory? »White pages = people finder = addresses =... »WWW-based and address directories »auctions through WWW

106 106 Internet indexes: evaluation criteria (Part 12) Is the search/query also submitted to another database to obtain more results? for instance: to a book database to obtain book descriptions besides WWW documents

107 107 !? Question !? Task !? Problem !? Why do different Internet search engines (in most cases) give different results for an identical search?

108 108 Internet indexes for citation searching: introduction Some Internet indexes / search engines allow you to search for documents / pages / URLs that link to a particular page, to some URL that you already know (such as one of the web pages that you have developed or that you have made available yourself). Linking to a URL is similar to citing an information source. Such search systems can be used to analyse web citations. Web citations are sometimes named sitations.

109 109 Internet indexes for citation searching: query syntax For details about the required query syntax, query formulation, see the online manual or help pages of the search system that you want to use.

110 110 Internet indexes for citation searching: link versus linkdomain Do not confuse links to a particular web page, using for instance a query like link:this_page.html with links to a whole web domain, using for instance a query like linkdomain: this_site

111 111 Internet indexes for citation searching: examples of systems AltaVista ! but note that Simple search and Advanced search may give different results Hotbot Google (Northernlight !) by using a query like link:this_page NOT url:this_site Examples

112 112 Internet indexes for citation searching: applications Citation searching on the WWW or on an intranet can be used »to get an idea of the importance, the fame, the impact of a particular web document, as measured by the number of links/citations to that page »to find out who has considered a particular page as interesting enough to make a link to »to find comments/criticisms on a particular web document

113 113 !? Question !? Task !? Problem !? Use a citation search engine.

114 114 Internet indexes for citation searching: evaluation criteria (1) Is usage free of charge? Is left truncation possible of the URL for which you want to find citations, so that citations to this and to underlying documents can be found in one action? Is right truncation possible of the URL for which you want to find citations, so that citations to this and to related documents on multiple sites can be found in one action?

115 115 Internet indexes for citation searching: evaluation criteria (2) Can self-citations and/or other documents be excluded from the search results in the query used to find citations? How complete is the coverage of the citation search system? Is the coverage of the search system good or poor for a particular geographic region? Is the coverage of the search system good or poor for a particular type of documents?

116 116 Internet indexes for citation searching: evaluation criteria (3) Up to date? Frequent updates? Only few dead / broken links? Is some form of relevance ranking of results offered? Which criteria are used for the ranking? Can the results be ordered according to date »of the file as noted by the server computer, or »of the most recent indexing of the file Can all the results (citing documents) from the same site be grouped together?

117 117 Internet indexes for citation searching: evaluation criteria (4) Is a good and detailed summary of each result made available? High stability and reliability? No large variations/fluctuations in the results from identical searches at different times. Good documentation and online help? Good help desk available? Can the search system provide updated results through electronic mail, as a current awareness tool?

118 118 !? Question !? Task !? Problem !? Compare Internet directories with Internet indexes (collection of data, coverage, ease of use,...) Compare Internet directories with Internet indexes (collection of data, coverage, ease of use,...)

119 119 Multi-threaded Internet search systems: scheme 1 User Client computer + WWW client program WWW server computer Internet WWW WWW server computers with Internet search systems In Out

120 120 Multi-threaded Internet search systems: scheme 2 User Client computer + Multi-threaded Internet search client program Internet WWW WWW server computers with Internet search systems In Out

121 121 Multi-threaded Internet search systems: scheme 1+2 User Client computer + WWW client program Client computer + Multi-threaded Internet search client program WWW server computer Internet WWW WWW server computers with Internet search systems In Out

122 122 Multi-threaded Internet search systems: vocabulary multi-threaded Internet search systems multiple search systems multi-search systems meta-search systems intelligent Internet search agents Internet meta-search tools...

123 123 Multi-threaded Internet search systems: relations User an Internet meta-search system Internet search system 1 Internet search system database 1 WWW pages Internet search system 2 Internet search system database 2

124 124 Multi-threaded Internet search systems: server-based or client-based Online accessible on a server in the Internet. On the client, meta-search software.

125 125 Examples Multi-threaded Internet search systems: server-based a collection is available from =

126 126 Examples Multi-threaded Internet search systems: client-based Example: Copernic

127 127 Multi-threaded Internet search systems: advantages + Saves time when otherwise more than only 1 Internet index would have to be used one after the other; for instance when searching for specific information that is hard to find in any single Internet index. + Some meta-search systems provide a useful integration of the results they get from the various primary search systems, with a removal of repeated results. + Some client-based meta-search systems show links among retrieved pages.

128 128 Multi-threaded Internet search systems: disadvantages (Part 1) - It is not always clear through which Internet indexes the meta-search system will search. - Not all meta-search systems can search all the major primary search systems. - The systems are often slower than a direct, primary search system.

129 129 Multi-threaded Internet search systems: disadvantages (Part 2) - Only a limited number of the results that can be obtained from the various Internet indexes are shown. - Some specific or advanced features of the individual search systems cannot be used through all the meta- search system, such as: »Boolean searching, »proximity searching, »field searching, »categorization of search results,...

130 130 Internet information sources Coverage of Internet directories and Internet indexes A global Internet index A global Internet directory

131 131 Global Internet search tools: a comparison Global Internet directories Only a limited selection of Internet sources Browsing information sources is easy Good for broad searches Global Internet indexes About 1/3 of the Internet is covered by an index Searching requires some skills and knowledge Good for specific, narrow searches Multi-threaded search systems These get information from directories and indexes Searching requires some skills and knowledge Good when even 1 index does not yield information

132 132 !? Question !? Task !? Problem !? Which information on the Internet is not covered by many searchable Internet indexes?

133 133 Internet indexes cover only a part of the Internet: introduction The visible part of Internet The hidden, invisible part of Internet and the WWW, (that is not searchable using a global index like, AltaVista, Google...)

134 134 Internet Internet indexes cover only a part of the Internet: scheme WWW Databases and file archives accessible through the Internet telnet ftp... telnet ftp... CGI, ASP,... Rapidly changing information, such as news Information accessible only when passwords are used Static indexable texts in the WWW ( = on HTTP server computers) covered partly by Internet indexes Word files PDF files

135 135 !? Question !? Task !? Problem !? Give an example of a database that is accessible through the WWW.

136 136 Internet indexes cover only a part of the Internet: conclusion for users When you want to retrieve information about a particular subject from the Internet, use not only WWW indexes, but use also other sources accessible through the Internet »anonymous ftp file archives, » based interest groups; Usenet newsgroups, »databases (book and journal bibliographies, library catalogues, archives of group messages, directories, atlases,…) »rapidly changing information, such as news »information accessible only when passwords are used

137 137 Gateways to Internet databases accessible free of charge Most Internet search engines search classical, static WWW pages and not databases accessible through the WWW. However, some systems offer a gateway to search databases on the Internet. Examples: (See also other more general directories/overviews/lists of Internet information sources.)

138 138 Finding multimedia files on the Internet Several public access search systems are available free of charge to search the Internet for multimedia files: »images / pictures (either artwork, either photos, or both) »sound / audio files (music, speeches,...) »video

139 139 Finding images on the Internet: introduction Several public access search systems are available free of charge to search for images / pictures (either artwork, either photos, or both) on the Internet. When searching for images, the search results from such a system offer not only links to the image files on the Internet, but also directly small versions of the images (so-called thumbnails).

140 140 Examples Finding images on the Internet: examples of search engines !!!http://alltheweb.com !http://gallery.yahoo.com/ !!!! or through !! (also audio and video, choose not the normal text search, but IMAGES in the user interface.)http://www.altavista.com/ !http://www.ditto.com/

141 141 Examples Finding images on the Internet: screen shot of a Google image search

142 142 !? Question !? Task !? Problem !? Use a specialised search engine to find images about a particular subject on the Internet.

143 143 !? Question !? Task !? Problem !? When you want to know if the contents of a particular WWW page has changed, then you can of course check/read/visit that page regularly. But is there a simpler way to track changes? When you want to know if the contents of a particular WWW page has changed, then you can of course check/read/visit that page regularly. But is there a simpler way to track changes?

144 144 Current awareness services focusing on WWW pages: introduction Tracking changes in one or more public access pages on the WWW or finding new pages, is possible »by using one of the available, suitable, programs loaded on your client workstation »through alert services based on a server on the WWW that track updates for the user/subscriber and send alerts by to the user/subscriber Few systems are free of charge.

145 145 Current awareness services focusing on WWW pages: Tracerlock can use one of several external Internet indexes with a simple search query given by you, to discover relevant changed or new WWW pages for you in the futurehttp://www.tracerlock.com/ Example

146 146 !? Question !? Task !? Problem !? Track the changes of a WWW page, by using a service free of charge on the WWW.

147 147 Online access information sources and services Public access book databases

148 148 Public access book databases: introduction Even in this age of Internet-based information sources, a lot of information is still distributed in the form of printed books. The contents of most books is (still) not available on the Internet. Most Internet search tools do NOT allow you to find out about the existence of books that may be interesting for you. So, specific search tools to find books can be useful.

149 149 Public access book databases: an overview (Databases by publishers.) Databases by book distributors / bookshops! Online public access library catalogues (Databases of computer-based versions of books.)

150 150 Public access book databases provided by bookshops To find currently available books, the bibliographic databases assembled by big bookshops are interesting. Several offer a good coverage and are accessible free of charge.

151 151 Book databases accessible free of charge: examples (Part 1) Amazon.com (US): note: amazon, NOT amazone Barnes and Noble (US): Blackwells on the Internet (International, academic books): Examples

152 152 Book databases accessible free of charge: examples (Part 2) VLB for books in German For books in French Boeknet - De Nederlandse Internet Boekhandel (Dutch) Examples

153 153 Free public access bibliographic book database + price comparisons Even comparisons of the catalogues of shops of books (as well as of music, movies and many other goods) are available free of charge. See for instance »http://www.bookfinder.com/http://www.bookfinder.com/ »http://www.dealtime.com/http://www.dealtime.com/

154 154 Example of an international public access dissertation database The dissertation database of UMI is available from: A part is available free of charge. Examples

155 155 Collection of links to public access book databases See for instance Internet directories like Yahoo! that lead to information about books. Examples

156 156 !? Question !? Task !? Problem !? Search for titles of books which are relevant for you, using an online database provided by a book publisher or bookshop.

157 157 Current awareness service for books Some systems can alert the user that a new book has been published when this fits the interest profile of the user. Such an interest profile can be stored on the server of the system in the form of »keywords, or »subject categories / subject fields Example:

158 158 Public access book databases: evaluation criteria(Part 1) Is usage free of charge? Wide coverage? Also for books in your preferred language? Specialized coverage for particular subjects? Up to date? Frequent updates? Abstracts, summaries, descriptions, tables of contents included? Full text indexing of each item in the database, so that full text searching is possible?

159 159 Public access book databases: evaluation criteria (Part 2) Field indexing, so that searching for the contents of a particular field is possible? for instance »the title »the date of publication »the author »the publisher »the language

160 160 Public access book databases: evaluation criteria (Part 3) Does the database producer improve retrieval by »adding subject terms, or »by classifying the books in categories Powerful search options: »truncation? stemming? »Boolean search combinations? proximity searching,…? »spelling check of your search terms? »translation of your search terms in several other languages?

161 161 Public access book databases: evaluation criteria (Part 4) Easy user interface? Is a user interface offered in your own language? Relevance ranking of results? Possibility to combine Boolean retrieval with relevance ranking of results? Can results be limited to a certain time period? Can the results be ordered according to date, size, origin,...?

162 162 Public access book databases: evaluation criteria (Part 5) Good presentation of each result? Does the system offer a current awareness service, sending information on new titles that may be of interest to you? Short response times?

163 163 Public access book databases: evaluation criteria (Part 6) Are other services offered from the same site or with the same interface? Is the system integrated with other services? Additional services can be »searchable databases of videos, of music CDs, CD-ROMs, DVDs, all for sale also »a subject directory for browsing, besides the database with index for searching »WWW-based and address directories »auctions through WWW

164 164 Online access information sources and services Library Online Public Access Catalogues = OPACs

165 165 Online Public Access Catalogues of libraries Mainly to find older books, the catalogues of libraries can be useful. Most are accessible online and free of charge.

166 166 Online Public Access Catalogues = OPACs: definition Online Public Access Catalogue: a term used to describe any type of computerized library catalog offered to the public by online login

167 167 !? Question !? Task !? Problem !? Which protocols are used by managers of catalogue systems to provide access to OPACs through the Internet?

168 168 Online Public Access Catalogues: Internet protocols used for access telnet (WAIS) Z39.50 WWW / http / html WWW / http / html + Z39.50 !

169 169 Online Public Access Catalogues: directories The most up-to-date directories and pointers to online access library catalogues are offered online by many WWW servers.

170 170 Online access library catalogues: The British Library Accessible online via WWW: Since 2000: Access free of charge Example

171 171 Online access library catalogues: The British Library: screenshot Example

172 172 !? Question !? Task !? Problem !? Search for titles of books which are relevant for you, in the British Library.

173 173 Online access library catalogues: The Library of Congress, U.S.A. >15 million books + >10 million other documents In Washington DC, U.S.A. Accessible online via WWW Access free of charge Example

174 174 !? Question !? Task !? Problem !? Search for titles of books which are relevant for you, in the Library of Congress catalogue.

175 175 Online access information sources and services Fee-based online public access information services

176 176 Types of online access information systems: free versus fee A lot of the information on the Internet is available free of charge, but another part is only accessible when a fee is paid to the producer and / or the distributor. Some organisations pay these fees for some sources and then organise access, so that the members of the organisation can retrieve and exploit the information as if it is free of charge. The first commercial computer systems that make information available online were born around Most of them are now also available through the Internet.

177 177 Fee-based online access services: examples (Part 1) Location of the computer(s)U.S.A. U.S.A. U.S.A. U.S.A., Taiwan, UK Switzerland U.S.A. Name America On Line OCLC Ovid Technologies CompuServe Cambridge Data-Star Dialog EBSCO Examples

178 178 Fee-based online access services: examples (Part 2) Location of the computer(s) U.S.A. U.S.A. U.S.A., The Netherlands,... Germany - U.S.A. - Japan The Netherlands... Name Elsevier ScienceDirect Factiva ISI (Web of Science, JCR,…) LexisNexis MSN (Microsoft) Prodigy Silver Platter STN Swets (e-journals)... Examples

179 179 Online information services: various names for similar systems (fee-based) online (access) information service (fee-based) online (access) computer service databank database vendor host computer aggregator...

180 180 Online information services: access methods Using generic, common communications software »through the telephone network (telephone + modem) »through X-25 data communication networks »through Internet, using client-server systems: telnet WAIS or Z39.50 http (WWW)! (Examples: (Using client software dedicated to the particular service)

181 181 Online information services: total size of their databases In 1999: The big host systems and the public access WWW pages offer a comparable quantity of information: WWW offered about 8 terabytes (= gigabytes) of text data (according to Lawrence and Lee Giles, Nature, 1999, Vol. 400, pp ) Dialog offered about 9 terabytes (= gigabytes) (in 1998) »6 billion pages of text »3 million images

182 182 Database producers and database hosts / distributors Some database producers distribute directly their own information from their own servers, and do not (only) rely on external host servers. Examples: »Cambridge Scientific Abstracts »Elsevier Companies / Organizations Database producers Hosts = Database vendors

183 183 Database hosts / distributors: evaluation criteria (Part 1) Contract required? A priori payment required? Stability / history / evolution / future of host? Low costs of data communication? Many databases available? Whole records available (or only parts)? Frequent updates? Whole database available? As one file or fragmented?

184 184 Database hosts / distributors: evaluation criteria (Part 2) Price of access? Price of information? Powerful search options: truncation, Boolean combinations, proximity searching,…? Can the indexes of more than one database be searched simultaneously? Speed of retrieval? Relevance ranking of results? Fast response? Accuracy of data communication? Clear output format?

185 185 Database hosts / distributors: evaluation criteria (Part 3) Online indication of costs? Easy user interface? Practice free of charge? Good manuals, documentation and online help? Training courses available? Quality? Good help desk available? Gateway service offered?...

186 186 Online use of external databanks: fixed cost factors Personnel ! Equipment and maintenance of equipment Contract with public data communication service Contracts with hosts Manuals about external databanks Directories of databases Training of personnel Journals about online information retrieval...

187 187 Online use of external databanks: variable cost factors Data communication Access to host / databank »(time spent online) »actions performed! Royalties for acquired information Storage of output / results »(Printing hard copies by the host) »Printing and/or storing on disk...

188 188 Searching indexes of more than one database simultaneously Application/purpose: Find most appropriate database, easily, fast and cheap

189 189 Online access versus CD-ROM databases: factors to compare (Part 1) User interface Availability of the required data on the medium? Time available for access? Hard- and software required for access Maintenance of the required hard- and software Dependence of data communication system for online access How many databases available on the same system?

190 190 Online access versus CD-ROM databases: factors to compare (Part 2) Searching in more than one database at the same time? Is the complete database accessible in one search? Flat fee for most CD-ROMs versus pay for what you get with many online databases Update frequency of database(s)...

191 191 Databases of online public access databases Example »Gale directory of databases ! Their coverage: »online access databases »(databases accessible on CD-ROM) »...

192 192 Databases of databases: Gale Produced in U.S.A. Not free of charge Available in various formats: »printed »on CD-ROM »online via the host systems Data-Star, Dialog, with a payment required for each use »online through the Internet through various hosts, for a fixed price per year to be paid in advance

193 193 !? Question !? Task !? Problem !? Identify databases which may be relevant for you, using a directory of online databases.

194 194 !? Question !? Task !? Problem !? When ASFA is available to you, develop a suitable search query and apply this to find documents about monitoring sea water pollution. Some advice: find and apply the relevant controlled terms (descriptors) from the thesaurus used by ASFA. When ASFA is available to you, develop a suitable search query and apply this to find documents about monitoring sea water pollution. Some advice: find and apply the relevant controlled terms (descriptors) from the thesaurus used by ASFA. Example

195 195 !? Question !? Task !? Problem !? When ASFA is available to you, develop a suitable search query and apply this to find documents that describe the state of the art in fishing by using poison in the lakes of Tanzania. Some advice: find and apply the relevant controlled terms (descriptors) from the thesaurus used by ASFA. Example

196 196 Online access information sources and services Online access databases about journal articles

197 197 Online access databases about journal articles: overview Thousands of fee-based online access databases offer bibliographies or full-texts of journal articles in particular subject domains. Only few large databases offer access to bibliographies of articles published in journals, free of charge.

198 198 Online access databases about journal articles: Northern Light Northern Light allows searching for the full text of articles from many journals/magazines. Searching is free of charge. Available from »http://www.northernlight.com/http://www.northernlight.com/ »http://www.nlsearch.com/http://www.nlsearch.com/ Payment is required to receive the full text of an article. Example

199 199 Online access databases about journal articles: Ingenta (1) Ingenta Journals allows you to search a bibliographic database of millions of journal articles, including titles, authors, in many cases abstracts. Searching is free of charge. Example

200 200 Online access databases about journal articles: Ingenta (2) Payment is required to receive the full text of an article. Ingenta has acquired Uncover in Available from »http://www.ingenta.co.uk/http://www.ingenta.co.uk/ »http://www.ingenta.com/http://www.ingenta.com Example

201 201 Online access databases about journal articles: allows you to search in a bibliographic database, NOT full-text (Journal articles, Journal issues, Books, Reports or Conferences, doctoral dissertations) at the Institut de l'Information Scientifique et Technique, France. Searching is free of charge. Available from Payment is required to receive the full text of an article. Example

202 202 Online access databases about journal articles: Infotrieve Infotrieve allows you to search free of charge in a bibliographic database of the articles of more than journal titles and conference proceedings, NOT full-text. Current awareness services are also offered free of charge. Available from Payment is required to receive the full text of a document. Example

203 203 !? Question !? Task !? Problem !? Search for titles of journal articles which are relevant for you, in a database provided free of charge.

204 204 Online access information sources and services Online information sources about journal titles

205 205 Online information sources about journal titles: introduction Besides directories / catalogs / overviews /databases / lists of electronic, computer-based, online accessible newsletters, newspapers, journals, and besides databases about published articles in journals (bibliographic databases), information is also available through the WWW about journal titles in general: their exact names, name changes, editors, prices, formats (printed or electronic online), full text availability online, …

206 206 Example Online information sources about journal titles: example Available free of charge:

207 207 Online access information sources and services Electronic newsletters and journals

208 208 Electronic newsletters and journals: introduction Since the end of the 1990s, electronic journals have become a new communication medium that cannot be neglected. Author / Sender Editor Reader / Receiver

209 209 Electronic newsletters and journals: variations on a theme We can distinguish several methods »of distribution and access »of formatting the information (PDF, HTML,…) »of pricing and licensing »of restricting access (authentication and authorization of legitimate users) »to integrate access to e-journals with access to other information sources

210 210 Electronic newsletters and journals: various types and the price of access We can distinguish various types: »equivalents of a version printed on paper Published almost simultaneously Print version published long time before electronic version = long delay for the electronic version »purely electronic publications Price of access: from free of charge to very expensive

211 211 Electronic newsletters and journals through the WWW The WWW has become the most important platform for access to electronic newsletters and journals.

212 212 !? Question !? Task !? Problem !? Which pricing schemes for access to electronic journals do you know?

213 213 Electronic newsletters and journals: pricing (Part 1) Several categories (pricing models) can be distinguished: »Free access for all »Access without extra costs besides the price for the print version; coupled with the printed version

214 214 Electronic newsletters and journals: pricing (Part 2) »Access with an extra cost on top of the price for the print version (for instance at 110%, or dependent on the number of potential users); coupled with the printed version »Access not free of charge, but access to the electronic version only, at a lower price than the price of the printed version (for instance at 80%, or dependent on the number of potential users); not coupled to the printed version

215 215 Electronic newsletters and journals: pricing (Part 3) »Access not free of charge; a printed version does not exist »One price for access to many or all of the electronic journals of an editor = package deal »Access not free of charge and the journal is one component of a bigger full-text database »Pay per view: payment for each article that is viewed »Payment for a license in the framework of a consortium of organisations (possible advantages of this approach: bundling of expertise, lower prices,…)

216 216 Electronic newsletters and journals: pricing (Part 4) »Access not free of charge; a group of authorised users selects a fixed number of articles from a collection of many journals and can then access these articles without further limit

217 217 Electronic newsletters and journals: authentication To control access to fee based electronic journals some method for authentication and authorization is used by publishers or distributors: »On the basis of the range of IP-addresses of the computer workstations used by the organisation »On the basis of a username and password couple that are constant, permanent or that are changed often by the information provider »Or based on a combination of those methods

218 218 Electronic newsletters and journals: authentication problems Up to now, the authentication methods are far from perfect: »Authentication by IP-address gives problems with users on external, unknown workstations outside the simple IP- address range »Authentication by passwords is complicated and passwords cannot be kept secret.

219 219 Electronic newsletters and journals: problems and challenges There is no central database with all article titles, summaries, and full contents. There is not even a central, complete and up to date directory of journal titles. There is no standard licensing/pricing method. Not all electronic journals are accessible through 1 user interface. Many passwords must be used. Archiving (By whom? For ever?)

220 220 Electronic newsletters and journals: integration with other sources It is not (yet) clear and straightforward how electronic journals should be integrated »in a library collection »in a library web site »in the catalogue database »in interlibrary lending (depends on licensing agreement for each individual journal)

221 221 Electronic newsletters and journals: integration and access methods Access can be possible through »A gateway offered by a subscription agent or the publisher »A commercial bibliographical database »A web-based static listing of journal titles »A web-based OPAC (for instance in the MARC 856 field) »A local searchable database for e-journals »Special linking mechanisms, such as SFX / OpenURL (commercialised by Ex Libris) COMPLEXITYCOMPLEXITY

222 222 Electronic newsletters and journals: more than one access method How should libraries and readers/users cope with the fact that many e-journals can be accessed in more than one ways, that is by hyperlinks starting from various information systems or services, while authentication and authorization is NOT fully automated for all those systems, once that a licensing agreement has been established? What mechanisms can offer support for this situation?

223 223 !? Question !? Task !? Problem !? Find out how you can efficiently access electronic journals from your institute.

224 224 Electronic newsletters and journals: usage statistics Statistical data related to usage: the collection, standardization and exploitation should be developed further.

225 225 !? Question !? Task !? Problem !? How to find out if the full text of a published printed article is also available online?

226 226 Directories of online access electronic archives of printed journals Several directories / catalogs / overviews are available of electronic, computer-based, online accessible archives of printed sources (newsletters, newspapers, journals,...): »Fulltext Sources Online (printed) taken over in 1998 by the publisher Information Today »Net.Journal Directory (printed) »...

227 227 Directories of online access electronic journals Several directories / catalogs / overviews / databases / lists are available of electronic, computer-based, online accessible newsletters, newspapers, journals,...: »http://www.coalliance.org/ejournalhttp://www.coalliance.org/ejournal »Scholarly journals distributed via the World Wide Web »Newjour: Electronic journals and newsletters

228 228 Online access information sources and services Computer-based information sources: criteria to evaluate their quality

229 229 Computer-based information sources: evaluation criteria (Part 1) Besides more general criteria applicable to all information sources, for those sources that are based on computers and networks we see the following criteria: Easy to navigate? »User-friendly information system? »Easy for users to orientate themselves within the resource and to find their way around it? »Is the resource organised into manageable chunks of information that can be browsed easily?

230 230 Computer-based information sources: evaluation criteria (Part 2) »Is a contents page or index offered that describes what is contained within the site? »Are there good navigational links within the pages (e.g. 'back', 'forward', 'home') »Are the links clearly labeled? »Is the navigation process supported by images? »Is there a single downloadable file for documents that exist as a series of separate pages? »Is there a search facility within the resource?

231 231 Computer-based information sources: evaluation criteria (Part 3) Good user support? »Good support that is offered to users to help them answer queries and problems that arise whilst using the resource? »Good computer-based, contextual help, documentation, training materials or tutorials? » contact(s) and telephone number(s) available?

232 232 Computer-based information sources: evaluation criteria (Part 4) Based on appropriate technologies? »Are technologies and standards used that will enable users to access and utilize all aspects of the resource? »Does the resource avoid that proprietary software should be used? »Does the resource avoid the use of proprietary extensions to HTML, which some browsers will not be able to recognize?

233 233 Computer-based information sources: evaluation criteria (Part 5) »Does the format allow access to the resource for all users, even for instance sight impaired and those who can only navigate by using the keyboard? Information integrity / High stability of the contents / Low volatility of the contents? »Is there adequate maintenance of the information content?

234 234 Computer-based information sources: evaluation criteria (Part 6) System integrity? »Site integrity relates to the stability of the site over time. This usually relates to the work of the site manager or web master. »Realise that individual sites can be moved or withdrawn at any time by those responsible for publishing information on the Internet, and that addresses, file structures, formats and interfaces can be altered without warning. »Is the site current and up to date?

235 235 Computer-based information sources: evaluation criteria (Part 7) »Is the site proven to be or expected to be durable in nature? »Is the site adequately administered and maintained?

236 236 Computer-based information sources: The Internet Detective A tutorial in English about how to assess the quality of WWW-based information resources can be accessed online free of charge through the WWW:

237 237 !? Question !? Task !? Problem !? Use The Internet Detective to learn more about assessing the quality of WWW-based information.

238 238 Online access information sources and services Future trends

239 239 Online access information: future trends An increasing amount of information becomes available online. A growing amount of this online information becomes available free of charge. The quality of server and client software is growing. A consequence is: An increasing number of end-users searching for information online.

240 240 Online access information: future trends regarding software From a mix of user interface + data offered both online by the server / host, to an increasing use of client-server architecture. Less usage of client software specific for one application, but increasing number of applications of generic, popular, widely distributed WWW client software. Increasing integration of various types of information sources, servers, and client software.

241 241 Online access information: conclusion In the case of simple information needs, the WWW and the search tools can work like magic. However, in the case of more complicated information needs, there is still is no magic button that brings you immediately to all the required information.


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