Computer and Internet Basics Unit A

Objectives Define Computers Explore Computer Functions Categorize Computers Examine Personal Computer Systems Explore data, information, and files

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

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

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

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

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

Categorizing Computers CostCost UsageUsage SizeSize CapabilityCapability

Less Powerful Computers Handheld computer/PDAHandheld computer/PDA Video game consoles Video game consoles PC/microcomputerPC/microcomputer WorkstationsWorkstations PC/microcomputerPC/microcomputer WorkstationsWorkstations

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

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

System Unit Power Supply Storage Devices Circuit Boards

Input/Output Devices MonitorKeyboardMouseModemPrinter Speakers/sound card Be able to identify each as input, output or both

Storage Devices Floppy disk drive Hard disk drive CD-ROM drive DVD drive ( reads CDs, too)‏ –DVD RW CD writer (cannot read DVDs)‏ –CD RW

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

Data Binary number system to define electronic data Each 0 or 1 is one bit Byte (8 bits)‏ = a character –“cat” = three bytes

Files Collection of data on a storage medium Data file (passive) Executable file (active)‏ –Potentially harmful (think Trojan Horse)‏ Filename and extension essay.doc word.exe dog.jpg

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: AndroidOS, BlackberryOS, Apple iPhone, Windows Mobile OS –Servers: Apache, UNIX, Microsoft IIS

Platform Mac and PC compatibility (sharing of files, etc.) is still an issue in 2011 Apple computer = Mac platform Original IBM computer = Windows or PC platform Microprocessor + Operating system

Application Software Microsoft PowerPointMicrosoft Excel Designed to carry out a particular task

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

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

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

Internet Resources E-commerce Web Sites: Research Chat Internet Radio Download Or Upload Internet Telephony (Vonage, Skype)‏ Internet Telephony (Vonage, Skype)‏ Instant Messaging Social Networking

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

Modem Internet Connections Dial-up connection (first commonly used, through phone lines and you could hear the computer actually dial the ISP's connect number)‏ Modem (56K and higher)‏ Cable Modems & Satellite –Network card and cable modem required –Always-on and 25 times faster than dial-up

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

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

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

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 options History list Favorites and bookmarks Edit and Find Microsoft Internet Explorer® and Netscape Navigator®

Search Engines KeywordsKeywords

Basics Account = Mailbox MessageAttachment HTML format Netiquette (top 10 online manners!)‏

System servers Store-and-forward technology Types –POP (Post Office Protocol) used via ISP –IMAP (Internet Messaging Access Protocol)‏ –Web-based: Hotmail, Yahoo, etc.Hotmail, Yahoo, etc.

System Your ISP You

TechTalk: Boot Process Power up ROM runs bootstrap program POST (Power-on self-test)‏ –Identifies and checks peripherals ROM loads operating system from hard disk into RAM Checks configuration and customization startup routines –Safe Mode if this process is not successful

Issue for Discussion How Private is ?

Summary Go back and read your objectives for this unit. –For example, the first objective states: “ Define Computers”“ Define Computers” –You should be able to say, without reading your notes, that a computer is a device that accepts input, processes data, stores data, and produces output. Get busy!