CMPF 124:Basic Skills for Knowledge Workers The Internet

CMPF124: Basic Skills for Knowledge Workers 2 Chapter Overview Welcome to Cyberspace: The Internet And World Wide Web Gaini Search Engines: Finding Information On The Web

Welcome to Cyberspace: The Internet And World Wide Web

CMPF124: Basic Skills for Knowledge Workers 4 The Internet Internet is a network of networks that connects computers across the country and around the world. Created by ARPAnet –DOD(Department of Defense), used by the military during world war. –ARPA(Advanced Research Projects Agency Network) 1994 Act of Congress opened Internet to commercial use

CMPF124: Basic Skills for Knowledge Workers 5 Each computer/node is independent of others Message/data travels different path each time it is sent Data is transmitted from one computer to another across the internet through a series of protocols known as TCP/IP (Transmission Control Protocol/Internet Protocol)

CMPF124: Basic Skills for Knowledge Workers 6 Capabilities of the Internet Internet provides 2 basic capabilities :- –World-wide information retrieval –World-wide communication Interactive User-determined

CMPF124: Basic Skills for Knowledge Workers 7 What’s On the Internet? Documents Graphics Weather TV/Movie Listings Music and Art Chat Rooms Businesses Mailings Lists Hotel/airline reservations Auctions Shopping

CMPF124: Basic Skills for Knowledge Workers 8 The World Wide Web The original language of the internet was difficult to use. You had to use a variety of programs (telnet, ftp, archie, gopher etc) to locate and download data. The programs were based on the Unix OS and you had to know the precise syntax of the commands within each program. No graphics and sound were available 1991 WWW - uses both hypertext (links) and Hypermedia (text, graphics, sound &video)

CMPF124: Basic Skills for Knowledge Workers 9 World Wide Web Subset of the total Internet Hypertext and/or hypermedia documents –Hypertext is a document that contains a hyperlink to another hypertext document. –Hypermedia provides links to graphic,sound and video files in addition to text files. Hyperlinks allow instant access to next site or document Client requests documents from Web server using hyperlinks

CMPF124: Basic Skills for Knowledge Workers 10 HyperText Transfer Protocol Data travels from client to server using the HTTP standards A browser allows you to access Web documents –Internet Explorer –Mozilla Firefox Start at site’s home page; click hyperlinks to jump to other Web pages Many sites include advertising

CMPF124: Basic Skills for Knowledge Workers 11 Hyperlinks Provide text, graphics, sound or video links Blue underlined fonts are unexplored Magenta links have been previously accessed

CMPF124: Basic Skills for Knowledge Workers 12 Web Browsing Example Start at and click Sports

CMPF124: Basic Skills for Knowledge Workers 13 Uniform Resource Locator (URL) Address bar shows URL (location) of the document Document Path (directory or folder) Web site (address of Web server) Means of access (HTTP)

CMPF124: Basic Skills for Knowledge Workers 14 Connecting to the Internet 2 basic ways to connect to the Internet. Connect through a LAN –Typical of college or business access –Faster than dial-up access –System configuration created and maintained for you

CMPF124: Basic Skills for Knowledge Workers 15 Connecting to the Internet (cont.) Dial up –Requires Internet Service Provider (ISP) and modem Modem is the hardware interface between your computer and the telephone. Subscriber dials ISP Internet Backbone ISP creates connection to Internet backbone

CMPF124: Basic Skills for Knowledge Workers 16 Connecting to the Internet Wireless technology –Allows user to have mobile connection. –Accomplished via public Wi-Fi networks. –A computer with wifi network cards connect wirelessly to a wireless router.

CMPF124: Basic Skills for Knowledge Workers 17 Internet Service Providers (ISP) ISP is a company that maintains a computer with permanent access to the Internet. Jaring Tmnet Maxis Broadband Yes 4G with Voice You need to pay certain amount of fee

CMPF124: Basic Skills for Knowledge Workers 18 How the Internet Works The backbone is operated by commercial providers such as TM. When you click a hyperlink, your request goes to your ISP, through a router to the backbone. –Router is a special-purpose computer that ensures each request(message) is sent to its correct destination.

CMPF124: Basic Skills for Knowledge Workers 19 TCP/IP Messages broken into packets TCP/IP sends packets by best available route and reassembles at destination Message reassembled by recipient’s client Message broken into packets and sent on multiple paths

CMPF124: Basic Skills for Knowledge Workers 20 Internet Architecture Layers

CMPF124: Basic Skills for Knowledge Workers 21 How Big is the Internet? No one knows! It’s expanding geometrically

Search Engines: Finding Information On The Web

CMPF124: Basic Skills for Knowledge Workers 23 Search Engines A program that systematically searches the Web for documents on a specific topic. You enter a query (a key word or phrase) into a search form, and the search engine scans its database to see which documents are related to the key word you requested. It will list the titles together with a link to each document.

CMPF124: Basic Skills for Knowledge Workers 24 Search Engines Many search engines available Each uses its own database of Web documents. Each database stores information about each document it contains, typically the document’s URL, key words that describe the document and selected information from the document. Use spiders to crawl the Web and find new sites and pages to add to search engine database

CMPF124: Basic Skills for Knowledge Workers 25 Enter a key-word query into search form Hits displayed on search results page Go from Web search to site search at relevant home page

CMPF124: Basic Skills for Knowledge Workers 26 Popular Web Search Engines URLSite

CMPF124: Basic Skills for Knowledge Workers 27 Logical Boolean Operators And, Or, Not –And ->includes all findings of both key word(s) –Or -> looks for only one of the specified key word (s) –Not -> allows you to exclude certain key word (s) Each search engine has its own syntax Use “advance search” function in search engine to enter Boolean operators

CMPF124: Basic Skills for Knowledge Workers 28 The Find and Save Commands Use the Find command to locate key word on current Web page Use Save Picture As command to save picture locally for later use in other documents Cite the site!

CMPF124: Basic Skills for Knowledge Workers 29 Find Command Edit Menu Find Command Searches within the document Faster Convenient

CMPF124: Basic Skills for Knowledge Workers 30 Pictures & Thumbnail Images Small Version Save Picture As Insert Picture –Insert menu –From File –Find Picture –Click Insert

CMPF124: Basic Skills for Knowledge Workers 31 File Compression Files are often compressed to reduce the file size, when sending a file from one location to another. –Such as when you are downloading software from the internet to your PC. Advantages : –Reduces the time for downloading. –Multiple files can be placed inside a single compressed file (also called an archive)

CMPF124: Basic Skills for Knowledge Workers 32 Compress (Zip) Files xxx.docyyy.doczzz.doc File Decompression Utility ProjectDocs.zip xxx.docyyy.doczzz.doc File Decompression Utility ProjectDocs.zip Sender creates zip file to store on Internet Receiver downloads zip file and unzips archive onto local drive Internet Server

CMPF124: Basic Skills for Knowledge Workers 33 Issues in Cyberspace Copyright Protection –Everything on the Internet is copyright protected unless in the public domain –You may use material from the Web in papers and presentations under the fair use doctrine –Cite your sources! Viruses –Use antivirus program and update it often for best protection

The End CMPF 124: Basic Skills for Knowledge Workers