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 E-mail 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

Two or more computers that are connected and share data and 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 instructions Input Program calculates, sorts modifies data Uses microprocessor or CPU Process Results of processing Reports, graphs, documents, pictures Printer or monitor Output Memory is temporary holding area (RAM) Storage is permanent (disk) Store

Categorizing Computers Cost Usage Size Capability

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

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.

Less Powerful Computers PC/microcomputer Workstations Handheld computer/PDA CD: video on PDA Videogame console Sony PlayStation®

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 Info web: supercomputer

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

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

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.

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

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.

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.

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

System Unit Power Supply Storage Devices Circuit Boards

Input/Output Devices Monitor Keyboard Mouse Modem Printer Speakers/sound card

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

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

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.

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.

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.

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

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

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 CD video: windows interface

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

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

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. Infoweb: cyberspace Infoweb: internet resources

Internet Terminology Backbone: defines main Internet routes TCP/IP: 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 CD screentour: web sites provides files

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

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 Infoweb: national ISPs Lab: making a dialup connection CD video: computer modems

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

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

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

World Wide Web Basics URL HTML (Hypertext Markup Language) No spaces and Case sensitive HTTP (Hypertext Transfer Protocol) HTML (Hypertext Markup Language) .htm or .html file extension Document name and filename extension Folder name Web server protocol standard http://www.cnn.com/showbiz/movies.htm

Search Engines CD screentour: search engines Keywords

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 Infoweb: browser Lab: browsing and searching Microsoft Internet Explorer® and Netscape Navigator®

E-mail Basics Account = Mailbox Message Attachment Most use HTML format Netiquette userid@computer Infoweb: netiquette Infoweb: e-mail client software Lab: using e-mail

E-mail System E-mail servers Store-and-forward technology Types POP (Post Office Protocol) used via ISP IMAP (Internet Messaging Access Protocol) Web-based like Hotmail Infoweb: web-based e-mail

E-mail System

Computer and Internet Basics End