1 Computer and Internet Basics Unit A

2 Objectives Define Computers Explore Computer Functions Categorize Computers Examine Personal Computer Systems Explore Data, Information, and Files

3 Objectives Introduce Application and System Software Define Internet Basics Connect to the Internet Understand World Wide Web Basics Use Browsers Understand Basics

4 A Computer is a device that accepts input processes data stores data produces output (all according to a series of stored instructions)

5 Computer system consists of: Hardware: microprocessor Peripheral devices: input and output Software: programs

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8 Computer Network Two or more computers that are connected and share data and programs LAN is a local area network

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10 Computer Functions Words, symbols, numbers, sound, pictures, program instructionsWords, symbols, numbers, sound, pictures, program instructionsInputInput Program calculates, sorts modifies dataProgram calculates, sorts modifies data Uses microprocessor or CPUUses microprocessor or CPUProcessProcess Memory is temporary holding area (RAM)Memory is temporary holding area (RAM) Storage is permanent (disk)Storage is permanent (disk)StoreStore Results of processingResults of processing Reports, graphs, documents, picturesReports, graphs, documents, pictures Printer or monitorPrinter or monitorOutputOutput

11 Categorizing Computers CostCost UsageUsage SizeSize CapabilityCapability

12 Computers to Fit Every Need Five basic categories –Mobile devices –Personal computers –Midrange servers –Mainframe computers –Supercomputers

13 Mobile Devices Very small computing devices. Usually based on a wireless phone or pager. Many can be used to access e- mail and Web pages.

14 Less Powerful Computers Handheld computer/PDAHandheld computer/PDA Videogame consoleVideogame console –Sony PlayStation® Videogame consoleVideogame console –Sony PlayStation® PC/microcomputerPC/microcomputer WorkstationsWorkstations PC/microcomputerPC/microcomputer WorkstationsWorkstations

15 More Powerful Computers Server –Supplies network computers with data Mainframe –Large, expensive, powerful, many users –Reliability, data security, central control important Supercomputer –Fastest and most powerful

16 Personal Computers, Cont’d. Desktop computers—small enough to fit on or next to a desk. Can use: –Desktop case –Tower case –All-in-one case

17 Personal Computers, Cont’d. Portable PCs—designed to be carried around. –Notebook computers –Tablet PCs (either slate or convertible) –Handheld computers (pocket computers)

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19 Personal Computers, Cont’d. PCs designed for just network use are referred to as network computers (NCs) or thin clients. Devices designed just for Internet access are called Internet appliances.

20 Midrange Servers Medium-sized computers, also called minicomputers or midrange computers. Fall between microcomputers and mainframes in processing power.

21 Mainframe Computers Standard choice for most large organizations. Specialize in high-volume processing of business transactions. Also called high-end servers or enterprise- class servers.

22 Supercomputers Used for applications that have extraordinary demands for processing power. Offer very fast speeds and extreme degrees of accuracy. Commonly created today by connecting hundreds of smaller computers to form a supercomputing cluster.

23 Computer System Computer +input devices + output devices + storage devices Peripherals

24 System Unit Power Supply Storage Devices Circuit Boards

25 Input/Output Devices MonitorKeyboardMouseModemPrinter Speakers/sound card

26 Storage Devices Floppy disk drive Hard disk drive CD-ROM drive DVD drive CD writer DVD writer

27 Data vs. Information Data (symbols) used by computers Information (meaningful) used by people

28 Software The programs or instructions used to tell the computer hardware what to do. System software allows a computer to operate and run application software. Application software performs specific tasks or applications.

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30 Data and Information Data = raw, unorganized facts. –Can be in the form of text, graphics, audio, or video. Information = data that has been processed into a useful form.

31 Computer Users and Professionals Computer users, or end users, are the people who use a computer to obtain information. Programmers are computer professionals whose job it is to write the programs that computers use.

32 Data Binary number system to define electronic data 0 or 1 Bit Byte (8 bits)

33 Files Collection of data on a storage medium Data file (passive) Executable file (active) Filename and extension Resume.doc Word.exe Image.jpg

34 System Software Helps the computer monitor itself in order to function efficiently Operating system –Master controller of all computer activities Popular operating systems –PCs: Microsoft Windows, Mac OS –Handhelds: Windows CE and Palm OS –Servers: Linus and UNIX

35 Platform Mac and PC compatibility is an issue Apple computer = Mac platform Original IBM computer = Windows or PC platform Microprocessor + Operating system

36 Application Software Designed to carry out a particular task Microsoft Excel Microsoft PowerPoint

37 Internet Basics Internet is a collection of local, regional, national and international computer networks that are linked together to exchange data and distribute processing tasks.

38 Internet Terminology Backbone: defines main Internet routes –Constructed and maintained by major telecommunications companies TCP/IP: –Transmission Control Protocol/ Internet Protocol

39 Internet Terminology Server software IP Address: unique number for each Internet computer Packets: small chunks of data ready to travel the Internet Router: helps send along the packets to correct destination

40 Internet Resources E-commerce Web Sites Chat Groups Internet Radio Download Or Upload Usenet Internet Telephony Instant Messaging P2P file sharing

41 Modem Internet Connections Dial-up connection via modem (56K) Cable modems –Network card and cable modem required –Always-on and 25 times faster than dial-up

42 Faster Internet Connections ISDN (Integrated Services Digital Network) –64K or 128K –Always-on and expensive DSL (Digital Subscriber Line) –Up to 125 times faster than dialup DSS (Digital Satellite Service) –500K Need proximity to a telephone switching station

43 Internet Service Provider (ISP) Provides internet access to businesses, organizations and individuals Provides telecommunications equipment User ID and password required Connects you to backbone account monthly fee Should have local access telephone numbers

44 World Wide Web Basics Files interconnected via hypertext Web pages make up a web site Home Page Links or hyperlinks Web servers

45 World Wide Web Basics URL –No spaces and Case sensitive –HTTP (Hypertext Transfer Protocol) HTML (Hypertext Markup Language) –.htm or.html file extension Document name and filename extensionFoldername Webservername Webprotocolstandard

46 Search Engines KeywordsKeywords

47 Using Browsers Can type URLs HTML tags tell browser how to display web page data Back, forward and stop buttons Setting a home page Print and copy options History list Favorites and bookmarks Edit and Find Microsoft Internet Explorer® and Netscape Navigator®

48 Basics Account = Mailbox MessageAttachment Most use HTML format Netiquette

49 System servers Store-and-forward technology Types –POP (Post Office Protocol) used via ISP –IMAP (Internet Messaging Access Protocol) –Web-based like Hotmail

50 System

51 Computer and Internet Basics End