Presentation on theme: "Introduction To Computer System"— Presentation transcript:
1 Introduction To Computer System جامعة أم القرىقسم السنة التحضيريهاعداد: أعضاء هيئة التدريس
2 Computer Generations First Second Third Fourth FIRST GENERATION - vacuum tubes used - slow I/O, punched cards- problems with heat and maintenance- used for payroll and record keeping- Univac ISECOND GENERATION- used transistors (developed at Bell Labs)- used tape for I/O- increased speed and reliability (threw off less heat)- used for billing and inventory- IBM 4101, Honeywell 200THIRD GENERATION- used integrated circuits- used magnetic disks for I/O- airline reservations and market forecasting- IBM 360, NCR 395
3 Computer Generations FOURTH GENERATION - used large-scale integrated circuits- increased storage capacity and speed- greater variety of I/O devices- tape, disk, microfilm, voice- used for simulation, CAD/CAM- IBM 3090, Sperry Univac 1100FIFTH GENERATION- ???- gallium arsenide instead of silicon?- true artificial intelligence?- bio-engineered computers?
6 Used discrete transistors IBM 704Used discrete transistors
7 IBM 709 MainframeLast of thevacuumtubecomputers,c. 1959
8 Digital Equipment Corp Left: DEC PDP-8, c. 1965Right: DEC PDP-11, c. 1970
9 Computer What is the Computer ? The Computer is a set of independent physical components and devices (Hardware), which have a specific job to do for each one and working together by Software to make up the computer system.Computer perform three main operations:
10 Computer Classifications (types) MicrocomputerMinicomputerMainframeSupercomputerThe four generally accepted classifications of computer size.Note that these are approximate, and not hard and fast - probably can find examples to disprove what I am saying!
11 Microcomputer Users: One Speed: Slow Price: $500 - $3,000 Size: desktop or smallerExamples: IBM PC, Apple ][, Apple Macintosh, Imac“personal computers”
13 Mainframe Computer Users: 50 + Speed: Fast Price: $500,000 - millions Size: refrigerator-sized on upExamples: IBM 3090, Unisys 2200company-wide (“enterprise”)
14 Supercomputer Users: a few Speed: very, very fast Price: $ millions Size: roomExamples: Cray, Fujitsuscientific uses
15 Understand the Terms Intelligent and Dumb Terminal. An intelligent terminal, for example a PC: -Performs a lot of the processing locallyYou could use a PC, linked to a mainframeA dumb terminal: -Has very limited processing capabilities itself, but allows you to connect to a large powerful computer such as a mainframe.When you process your data from the dumb terminal, it is the mainframe at the other end of the network that is performing all the calculations.
28 Hardware Organization CPUmemoryhard driveغير مطلوبة فقط للفهم
29 Mother-Board (or Main Board) غير مطلوبة فقط للفهمغير مطلوبة فقط للفهمCPURAMROM
30 Hardware Organization CPUmemorymotherboardhard driveغير مطلوبة فقط للفهم
31 Central Processing Unit (CPU) A specific chip or the processora CPU's performance is determined by the rest of the computers circuitry and chips.The Central Processing Unit (CPU) performs the actual processing of dataThe speed (clock speed) of CPU measured by Hertz (MHz)
32 The CPU consists of : Control Unit (CU) Arithmetic and Logical Unit (ALU)Some Registers
33 Central Processing Unit (CPU) Control Unit (CU)Arithmetic LogicUnit (ALU)Registers
34 coordinates all activities of the computer by: The Control Unit (CU) :coordinates all activities of the computer by:Determining which operations to perform and in what order to carry them out.The CU transmits coordinating control signals to other computer components.
35 consists of electronic circuitry to perform: The ALU :consists of electronic circuitry to perform:Arithmetic operations (addition, subtraction, multiplication and division)Logical operations (and, or, not, …) and to make some comparisons (less-than, equal, … etc.)
36 Hardware Organization CPUmemorymotherboardhard driveغير مطلوبة فقط للفهم
37 Primary MemoryMemory (fast, expensive, short-term memory): Enables a computer to store, at least temporarily, data, programs, and intermediate results.Two general parts:RAMROM
38 Know How Computer Memory Is Measured BitAll computers work on a binary numbering system, i.e. they process data in one's or zero's. This 1 or 0 level of storage is called a bit.ByteA byte consists of eight bits.KilobyteA kilobyte (KB) consists of 1024 bytes.MegabyteA megabyte (MB) consists of 1024 kilobytes.GigabyteA gigabyte (GB) consists of 1024 megabytes.
40 RAM (Main Memory) its a primary storage or random access memory (RAM). it temporarily holds data and programs for use during processing (volatile)Any information stored in RAM is lost when the computer is turned off.RAM is the memory that the computer uses to temporarily store the information as it is being processed. The more information being processed the more RAM the computer needs.RAM consists of locations or cells. Each cell has a unique address which distinguishes it from other cells.
41 ROM: Read Only Memory ROM is part of memory Programmed at manufacturing timeIts contents cannot be changed by usersIt is a permanent storeQ: Mention some examples of ROM?A: (PROM & EPROM )
42 Other Kind of Memory PROM: Programmable Read Only Memory. EPROM: Erasable Programmable Read Only MemoryCache MemoryRegisters: not part of the main memory.Q : Registers are part of “ …… ” ?
43 Secondary StorageStores data and programs permanently: its retained after the power is turned offExamplesHard Drive (Hard Disk)Located outside the CPU, but most often contained in the system cabinetFloppy DiskOptical Laser DiscsCD-ROM, CD-RW, and DVD
45 Common Secondary Media DiskettesData represented as magnetic spots on removable flexible plastic disksMost common size is 3 1/2 inches, in a rigid plastic caseDisk drive holds the diskette, reads or retrieves the data and writes or stores data
46 Common Secondary Media Hard driveData is represented magnetically as with diskettesNormally more than one rigid platter in a sealed unitThese disks are not removableSignificantly more capacity and faster operating than diskettes
47 Optical Laser Discs CD ROM & DVD’s Data is represented as pits and landsSome kinds are read only (CD-ROM) and some Kinds are rewritable (CD-RW)Significantly more capacity and faster operating than diskettesDVD: Digital Video Disk
48 Approximate printed 8.5 x 11 inch pages Common Secondary MediaApproximate printed 8.5 x 11 inch pagesAmount of storageDisk size180 pages360 Kb5.25 low density360 pages720 Kb3.5 low density600 pages1.2 Mb5.25 high density720 pages1.44 Mb3.5 high densitya small library700 MBCDa feature length movie8.5 GBDVD
49 Common Secondary Media tapesPanasonic's LS inch diskettesIomega's Zip & Jazz disksVCR tape (Video Cassette Recorder )Flash USB disksMMC (Multi Media Card )SD
50 Hardware Organization CPUmemoryhard driveغير مطلوبة فقط للفهمOutput …
51 CPUOutput DevicesPieces of equipment that translate the processed information from the CPU into a form that humans can understand.Processedinformation
52 Output Devices Monitors Printers Dot matrix printersInk jet printersLaser printersSound Blasters (Sound Card By Creative Lab)Controlling other devices
53 Software The instructions that tell the computer what to do Application Software - helps end-users perform general purpose tasksSystem Software - enables application software to interact with the computer
54 System Software System Software Operating System The most important is theOperating SystemExamples of operating systems:Windows XP, DOS, Apple, UNIX
55 System SoftwareThe software that controls everything that happens in a computer.Background software, manages the computer’s internal resourcesResources examples : CPU, RAM , I/O devices, …
56 Among other things, the operating system: All hardware and software are under the control of the operating system.Among other things, the operating system:Determines how valuable RAM is allotted to programs.Performs tasks related to file management.Sets priorities for handling tasks.Manages the flow of instructions, data and information to and from the processor (CPU).
57 Examples of Microcomputer Operating System Software DOS - original standard for IBM compatiblesWindows - a graphical operating environmentWindows VISTA, XP, millennium, 2000, 98, and 95Continue …
58 Examples of Microcomputer Operating System Software Cont. Windows NT - for powerful workstations & networksOS/2 - competitor to Windows 2000Macintosh Operating SystemUnix - originally for minicomputers, now used on microcomputers and Internet serversQuestion: List some examples of operating systems ?
59 Application Software Packaged Custom Packaged - “off the shelf”, pre-written programs ( General purpose)Custom - written for an organization’s specific purpose (Special purpose)
60 Application Software – Basic Tools Word processors– example: Microsoft wordSpreadsheets-- example: Microsoft ExcelDatabase managers-- example: Microsoft AccessGraphics-- example: PhotoshopSpreadsheets: Computer software that allows the user to enter columns and rows of numbers in a accounting book like format.
62 Talk Flow! Introduction to the Internet HTML Using search engines Brief historyExplaining basic protocolsNaming on the netHTMLUsing search enginesQuestions
63 What is the Internet? A Network of Computer Networks Started as early as the 1960sBuilt to work even if a large part of the network fails
64 Network Network Internet Internet Internet OSPF (Open Shortest Path First) or IS-IS (Intermediate System-to-Intermediate System).InternetInternet
65 World Wide Web? A part of the Internet www1, www2 etc.,Based on hypertext and hypertext transfer protocol (HTML & HTTP)Supports multiple media - MultimediaInteractive, dynamic HTML
66 Brief History of the Internet 1960s - Department of Defense initiative ARPANETARPA launches the Internetting Project to explore the possibilities of linking networks1980 – First Virus halts the Internet1984 – DNS Introduced (Names rather than numbers)1999 – Internet Banking
67 Services through the net Major services:– Electronic MailFTP – File Transfer ProtocolGopher (TCP/IP)NewsgroupsTelnet – Remote sessionWAIS – Wide Area Information SystemWWW – World Wide Web
68 How to read an URLspecifies the protocol as http, the host or WWW server as uqu.edu.jo and the document as /cs100/windows.htm
69 Getting a Domain Name? Top Domains: edu – Educational Institutions com – Company / Commercial Organizationsorg – Non-profit Organizationsnet – Network, network of sitesmil – Military Installationsgov – Government sitesSub Domains:sa- Saudi Arabiajo - Jordanuk – United Kingdom.biz .info
70 Identifying a PC on the Internet IP Number(Intranet, Local IP)To find your IP number on WindowsExecute ipconfig on your command prompt – XP
71 HypertextHypertext, a method of preparing text that allows readers to choose their own pathways through the material, is invented by Ted Nelson.The underlined word represents a hyperlink that lets the reader click and jump to a new page.Provides interactive browsing
72 BrowsersBrowser software allows us to view, hear, retrieve information created for the webInternet Explorer, Netscape Navigator, Lynx
74 Computer VirusesA computer virus is an application program designed and written to destroy other programs.It has the ability to:Link itself to other programsCopy itself (it looks as if it repeats itself)
76 Viruses and Virus Protection A virus programInfects programs, documents, databases and more …It is man-madeIt can hide and reproduceIt can lay dormant (inactive) and then activateAnti-virus programs can help
77 Viruses and Virus Protection (2) A variety of highly contagious “viruses” can spread from computer to computer, much the way biological viruses do among human beings.Just as a virus can infect human organs, a computer virus can infect programs and databases. It can also hide duplicates of itself within legitimate programs.
78 Viruses and Virus Protection(3) These viruses, which are programs, reside on and are passed between magnetic disks.Most people who write and circulate virus programs fall into two groups.The first group uses viruses to show off for their peers.The second, and far more dangerous group, creates viruses with malicious intent.
79 Sources of Computer Viruses Three primary sourcesThe InternetVia downloads and exchangesDiskettesExchanging disksComputer networksCan spread from one network to another
80 How do you know if you have a virus? Lack of storage capabilityDecrease in the speed of executing programsUnexpected error messagesHalting the system
81 Virus ProtectionThe software package distributed with new PCs always includes an antiviral program. The best way to cope with viruses is to recognize their existence and use an antiviral, or antivirus program.
82 Some tips that will help minimize your vulnerability to viruses: Delete s from unknown or suspicious, untrustworthy (unreliable) sources, especially those with files attached to an .Never open a file attached to an unless you know what it is, even if it appears to come from a friend.Download files from the Internet only from legitimate and reputable sources.Update your antivirus software at least every two weeks as over 200 viruses are discovered each month.Backup your files periodicallyTraditionally virus protection has been at the PC or client level. However, this may change as companies look to network and Internet service providers for more services.
83 Computer Ethics You shall not use a computer to harm other people. You shall not snoop around in other people's computer files.You shall not use a computer to steal.You shall not use other people's computer resources without authorization or proper compensation.You shall always use a computer in ways that show consideration and respect for your fellow humans.
84 Computer Uses 1- Supermarkets: Use a bar code reader. 2- Libraries: Use computers to search for books; to record bookslending and return ….3- Banks: Enable customers to access their accounts via ATM.4- Plastic Cards: Used in computer system to facilitate customerslife (mobile, telephone and credit cards)5- Electronic Commerce: Uses Internet in business forpurchasing, payment, or reservations.6- Touch Screens: Allow unskilled customers to accessinformation easily.7- Hospitals: Use computers to store records of patients and tohelp in the diagnosis and analysis of the treatment.8- Cars: Computers are used to display maps and giveinstructions to the driver.