Mastering the Internet, XHTML, and JavaScript Chapter 2 Web Browsers

2Chapter 2 - Web BrowsersOutline Goals and Objectives Goals and Objectives Chapter Headlines Chapter Headlines Introduction Introduction Finding a web page Finding a web page Browser Tasks Browser Tasks The two browsers The two browsers Browser window structure Browser window structure Internet Explorer Internet Explorer Netscape Communicator Netscape Communicator Opera Opera Crazy Browser Managing web pages Browser Cache Plug-ins Bookmarks History list Customization Security Wireless browsing Summary

3Chapter 2 - Web Browsers Goals and Objectives Goals Goals Understand and master the use of web browsers, to make surfing the web a more pleasant and productive experience Objectives Objectives Browser Tasks Browser Tasks Browser Window Structure Browser Window Structure Microsoft Internet Explorer Microsoft Internet Explorer Netscape Communicator Netscape Communicator Opera and Crazy Browser Opera and Crazy Browser Managing browsers: cache, plug-ins, and customization Managing browsers: cache, plug-ins, and customization Managing surfing: bookmarks, privacy, and security Managing surfing: bookmarks, privacy, and security Browsers for hand-helds Browsers for hand-helds

4Chapter 2 - Web Browsers Chapter Headlines 2.1 Introduction 2.1 Introduction You need a web browser to view web pages You need a web browser to view web pages 2.2 Finding a web page 2.2 Finding a web page The browser uses the URL of the web page to locate its web server computer The browser uses the URL of the web page to locate its web server computer 2.3 Browser Tasks 2.3 Browser Tasks Common browser tasks are viewing, navigation, downloading files, and printing Common browser tasks are viewing, navigation, downloading files, and printing 2.4The Two Browsers 2.4The Two Browsers Internet Explorer is widely used and Netscape is second Internet Explorer is widely used and Netscape is second 2.5 Browser Window Structure 2.5 Browser Window Structure All browsers have title bar, menu bar, toolbars and status bar All browsers have title bar, menu bar, toolbars and status bar 2.6Internet Explorer 2.6Internet Explorer Fast and versatile browser but has no tabs, filters, or skins Fast and versatile browser but has no tabs, filters, or skins

5Chapter 2 - Web Browsers Chapter Headlines 2.7Netscape Communicator 2.7Netscape Communicator Comes in two versions: 4.8 and 7.01 Comes in two versions: 4.8 and Opera 2.8Opera Claims to be the fastest browser on earth and has skins too Claims to be the fastest browser on earth and has skins too 2.9Crazy Browser 2.9Crazy Browser Imitates IE, but is a tabbed browser, and has popup filters and killers Imitates IE, but is a tabbed browser, and has popup filters and killers 2.10Managing Web Pages in a Browser 2.10Managing Web Pages in a Browser Each page has URL, XHTML file, and content display Each page has URL, XHTML file, and content display 2.11 Browser Cache 2.11 Browser Cache It speeds up downloading of web pages It speeds up downloading of web pages 2.12Plug-ins 2.12Plug-ins It enables rendering of many different file types It enables rendering of many different file types

6Chapter 2 - Web Browsers Chapter Headlines 2.13Bookmarks 2.13Bookmarks It enables rendering of many different file types It enables rendering of many different file types 2.14 History List 2.14 History List Use browser history list to trace your past navigation experience Use browser history list to trace your past navigation experience 2.15 Customization 2.15 Customization Change browser colors, fonts, and other settings to suit your use and style Change browser colors, fonts, and other settings to suit your use and style 2.16 Security 2.16 Security HTTPS, digital keys, and certificates protect data on internet HTTPS, digital keys, and certificates protect data on internet 2.17 Wireless Browsing 2.17 Wireless Browsing Ability to Sync handhelds for mobility Ability to Sync handhelds for mobility

7Chapter 2 - Web BrowsersIntroduction A web browser is a computer program that displays web page content A web browser is a computer program that displays web page content The user can specify the requested web page, by typing or clicking on a link, in a browser The user can specify the requested web page, by typing or clicking on a link, in a browser Browser can, then, locate and retrieve relevant web pages from servers Browser can, then, locate and retrieve relevant web pages from servers Browser window is like the window of any other computer application Browser window is like the window of any other computer application

8Chapter 2 - Web Browsers Finding a Web-page 1. Type the page URL 2. Browser sends URL to DNS server which replies with IP address of requested server 3. TCP/IP packets go to the server through routers 4. Web server, upon receiving the packets, locates the file and sends it to your browser through routers

9Chapter 2 - Web Browsers Browser Tasks The following are important browser tasks: ViewingNavigatingDownloadingPrinting tools

10Chapter 2 - Web Browsers Two Browsers Internet Explorer (IE) and Netscape Communicator (NC) are two important browsers To download IE go to To download NC go to

11Chapter 2 - Web Browsers Browser Window Structure A browser window has several bars on top of the window and one on the bottom of the window Title bar : displays the title of current web page Title bar : displays the title of current web page Menu bar : contains the pull down menus Menu bar : contains the pull down menus Navigation bar : to navigate through web-pages Navigation bar : to navigate through web-pages Address bar : to type URL addresses Address bar : to type URL addresses Status bar : displays messages about the progress of current tasks Status bar : displays messages about the progress of current tasks Display area : displays the web page content Display area : displays the web page content

12Chapter 2 - Web Browsers Browser Window Structure

13Chapter 2 - Web Browsers Internet Explorer Menus: File File Edit Edit View View Favorites Favorites Tools Tools Help Help Toolbars: Standard buttons Address bar (URL) Links toolbar Status bar

14Chapter 2 - Web Browsers Netscape Communicator Menus: File File Edit Edit View View Go Go Communicator Communicator Help Help Toolbars: Navigation toolbar Address bar (URL) Personal toolbar Status barModules: Navigator Navigator Inbox Inbox Newsgroups Newsgroups Composer Composer Address book Address book Instant messenger Instant messenger

15Chapter 2 - Web Browsers Netscape Communicator

16Chapter 2 - Web Browsers Netscape Communicator

17Chapter 2 - Web BrowsersOperaMenus: File File Edit Edit View View Navigation Navigation Bookmarks Bookmarks Mail Mail Window Window Help Help Toolbars: Main bar Navigation bar Address bar Personal toolbar Page bar Status bar Can be downloaded at Can be downloaded at When it crashes it starts where it left off When it crashes it starts where it left off

18Chapter 2 - Web BrowsersOpera

19Chapter 2 - Web Browsers Crazy Browser Menus: File File Edit Edit View View Favorites Favorites History History Groups Groups Options Options Tools Tools Tabs Tabs Help Help Toolbars: Navigation bar Address bar Links bar Status bar

20Chapter 2 - Web Browsers Managing web pages Managing web pages deals with three aspects: Managing web pages deals with three aspects: URL URL XHTML file XHTML file Display in browser Display in browser A user can save a web page URL by making it a favorite in IE or a bookmark in NC A user can save a web page URL by making it a favorite in IE or a bookmark in NC A user can print the web page he is viewing by using the Print button A user can print the web page he is viewing by using the Print button A user can save the web page by using Save As… option from the File menu A user can save the web page by using Save As… option from the File menu

21Chapter 2 - Web Browsers Browser Cache A browser cache speeds up the retrieval and display of web pages that are being re-visited during a session A browser cache speeds up the retrieval and display of web pages that are being re-visited during a session Browsers use two types of caching schemes Browsers use two types of caching schemes Memory cache Memory cache Disk cache Disk cache Memory cache saves web pages during its current session Memory cache saves web pages during its current session Disk cache saves web pages from its previous session Disk cache saves web pages from its previous session When a page is requested, the browser first checks its memory cache and then disk cache. When a page is requested, the browser first checks its memory cache and then disk cache. Browser also checks for updates Browser also checks for updates

22Chapter 2 - Web BrowsersPlug-ins Plug-ins are programs that run within the browser Plug-ins are programs that run within the browser Plug-ins appear to be a part of the browser even though they are separate programs Plug-ins appear to be a part of the browser even though they are separate programs The browser informs the user whenever a plug-in is needed for a web page The browser informs the user whenever a plug-in is needed for a web page They are easy to install They are easy to install Examples include: Examples include: Adobe Acrobat Reader : to view.pdf files Adobe Acrobat Reader : to view.pdf files Macromedia Shockwave : plays animation and sound Macromedia Shockwave : plays animation and sound Macromedia Flash : to view animations Macromedia Flash : to view animations Apple Quicktime : plays text, animations, video, and sound Apple Quicktime : plays text, animations, video, and sound

23Chapter 2 - Web BrowsersBookmarks A bookmark is a saved link to a web page A bookmark is a saved link to a web page User can name the bookmarked links User can name the bookmarked links E.g.my bank account, my home page E.g.my bank account, my home page Bookmarks in one browser/machine cannot be visible in another browser/machine Bookmarks in one browser/machine cannot be visible in another browser/machine Bookmark managing task include: Bookmark managing task include: Adding Adding Deleting Deleting Organizing Organizing IE refers to bookmarks as Favorites IE refers to bookmarks as Favorites

24Chapter 2 - Web Browsers History List History allows users to retrace their surfing steps History allows users to retrace their surfing steps History can be: History can be: Short term Short term Long term Long term Short tem history is related to Memory cache Short tem history is related to Memory cache Long term history is related to Disk cache Long term history is related to Disk cache CRTL + H keyboard shortcut usually displays browser history list CRTL + H keyboard shortcut usually displays browser history list Some browsers also have separate History button Some browsers also have separate History button

25Chapter 2 - Web BrowsersCustomization Browsers are customizable by users to fit their specification and style Browsers are customizable by users to fit their specification and style The user can customize: The user can customize: Default options Default options Default web page Default web page Fonts Fonts Colors Colors Toolbars Toolbars Display of images Display of images Java and Javascript Java and Javascript Style sheets Style sheets Cookies options Cookies options Configure mail and news groups server Configure mail and news groups server Change the size of cache Change the size of cache

26Chapter 2 - Web BrowsersSecurity Security is important to prevent unauthorized access to the information passed between clients and servers Security is important to prevent unauthorized access to the information passed between clients and servers Security over the internet is ensured by using encryption and decryption techniques Security over the internet is ensured by using encryption and decryption techniques Encryption and decryption technology is implemented by using Secure Sockets Layer (SSL) developed by Netscape Encryption and decryption technology is implemented by using Secure Sockets Layer (SSL) developed by Netscape SSL is a communication protocol and uses the HTTPS protocol SSL is a communication protocol and uses the HTTPS protocol Encryption systems incorporate: Encryption systems incorporate: Public and Private Key Public and Private Key Digital Certificate Digital Certificate

27Chapter 2 - Web Browsers Wireless Browsing Wireless browsing is the browsing activity on miniature screens of small electronic devices Wireless browsing is the browsing activity on miniature screens of small electronic devices Some examples of devices where wireless browsing is incorporated are: Some examples of devices where wireless browsing is incorporated are: Pocket PCs Pocket PCs Hand-held PCs Hand-held PCs Cell phones Cell phones PDAs PDAs Wireless browsing can be online or offline Wireless browsing can be online or offline Offline wireless browsing is called sync for short, in which web pages are downloaded on the device for viewing them later Offline wireless browsing is called sync for short, in which web pages are downloaded on the device for viewing them later Wireless browsing is different for reason such as screen size and disk space and have special browsers Wireless browsing is different for reason such as screen size and disk space and have special browsers

28Chapter 2 - Web Browsers Wireless Browsing

29Chapter 2 - Web BrowsersSummary A web browser provides access to a web page A web browser provides access to a web page Browsers enable internet users to perform useful tasks Browsers enable internet users to perform useful tasks Internet Explorer and Netscape Communicator are two major browsers Internet Explorer and Netscape Communicator are two major browsers A browser window has a generic structure A browser window has a generic structure Menus and Toolbars in any browser allow the user to change settings and perform browser tasks Menus and Toolbars in any browser allow the user to change settings and perform browser tasks Browser cache speeds up the display of re-visited web pages Browser cache speeds up the display of re-visited web pages Plug-ins run within the browser Plug-ins run within the browser Browsers can be customized to suit the user style Browsers can be customized to suit the user style Security is a major issue with internet communications Security is a major issue with internet communications Wireless browsing is different from desktop browsing Wireless browsing is different from desktop browsing