1.1 WEB CONCEPTS AND TERMINOLOGY1.1 WEB CONCEPTS AND TERMINOLOGY1.1.1 1.1.1 WEB CONCEPT AND RELATIONSHIP BETWEEN LAN WEB CONCEPT AND RELATIONSHIP BETWEEN LAN ( CLIENT/SERVER) AND THE INTERNET( CLIENT/SERVER) AND THE INTERNET

What is the Internet?What is the Internet? The The InternetInternet also called also called NetNet is a worldwide collection is a worldwide collection

of computer networks that links together millions of of computer networks that links together millions of computers used by business, the government, computers used by business, the government, educational institutions, organizations and individuals educational institutions, organizations and individuals using modems, telephone lines, television cables and using modems, telephone lines, television cables and other communication devices and media.other communication devices and media.

A A NetworkNetwork is a group of two or more computers that are is a group of two or more computers that are connected together to share resources and information. connected together to share resources and information.

The The Internet BackboneInternet Backbone is a collection of high speed data is a collection of high speed data lines that connect major computer system located around lines that connect major computer system located around the wordthe word

An An Internet service provider (ISP)Internet service provider (ISP) is a company that has a is a company that has a permanent connection to the Internet backbone. ISPs utilize permanent connection to the Internet backbone. ISPs utilize high- or medium-speed data lines to allow individuals and high- or medium-speed data lines to allow individuals and companies to connect to the backbone for access to the companies to connect to the backbone for access to the internet.internet.

User with computers connected to the Internet can access a User with computers connected to the Internet can access a variety of services such as e-mail, World Wide Web etc. variety of services such as e-mail, World Wide Web etc.

The World Wide Web or WebThe World Wide Web or Web The part of the internet that supports multimedia The part of the internet that supports multimedia

and consists of a collection of linked documents.and consists of a collection of linked documents. To supports multimedia, the Web relies on the To supports multimedia, the Web relies on the

Hypertext Transfer Protocol (HTTP), which is a set Hypertext Transfer Protocol (HTTP), which is a set of rules for exchanging text, graphic, sound, video, of rules for exchanging text, graphic, sound, video, and other multimedia files.and other multimedia files.

The linked documents, or pages of information, on The linked documents, or pages of information, on the Web are know as the Web are know as Web pagesWeb pages. .

Web pagesWeb pages A Web page can contain text, graphic, sound, and A Web page can contain text, graphic, sound, and

video, as well as built built-in connections to other video, as well as built built-in connections to other document.document.

Web siteWeb site A Web site is a related collection of Web Pages that A Web site is a related collection of Web Pages that

is created and maintain by an individual, company, is created and maintain by an individual, company, educational institution, or other organization.educational institution, or other organization.

Types of Web PagesTypes of Web Pages

- The The (6) SIX(6) SIX basic types of Web pages are : basic types of Web pages are :1) 1) PortalPortal

- A portal Web page offers a variety of Internet services A portal Web page offers a variety of Internet services from a single, convenient location.from a single, convenient location.

- Most portals offer the following free services : search Most portals offer the following free services : search engine; local, national, and worldwide news, sports and engine; local, national, and worldwide news, sports and weather, free personal Web pages, reference tools such as weather, free personal Web pages, reference tools such as yellow pages, stock quotes, and maps; shopping malls and yellow pages, stock quotes, and maps; shopping malls and auction; e-mail, instant messaging, newsgroup or message auction; e-mail, instant messaging, newsgroup or message board, calendar, and chat rooms or forum.board, calendar, and chat rooms or forum.

- E.g : Yahoo!, Alta Vista, America Online, Euroseek, E.g : Yahoo!, Alta Vista, America Online, Euroseek, Excite, Google, HotBot, Lycos etc.Excite, Google, HotBot, Lycos etc.

2) 2) NewsNews- A news Web page contains newsworthy material A news Web page contains newsworthy material

including stories and articles relating to current events or including stories and articles relating to current events or issues, life, money, sports and the weathersissues, life, money, sports and the weathers

- E.g : ESPN, Utusan Melayu.com, Beritaharian.com etc.E.g : ESPN, Utusan Melayu.com, Beritaharian.com etc.

3) 3) InformationalInformational- A Informational Web page contains factual information A Informational Web page contains factual information

that providing infromation such as cencus data, tax codes, that providing infromation such as cencus data, tax codes, public transportation schedules and published research public transportation schedules and published research finding.finding.

- E.g : AirAsia.com, emeraldinsight.com E.g : AirAsia.com, emeraldinsight.com

4) 4) Business / MarketingBusiness / Marketing- A Business / Marketing Web page contains contents that A Business / Marketing Web page contains contents that

promotes or sells products or services.promotes or sells products or services.- E.g : AT&T, Dell Computer Corporation, General Motor E.g : AT&T, Dell Computer Corporation, General Motor

Corporation, Kraft Foods Inc.., Walt Disney, etc.Corporation, Kraft Foods Inc.., Walt Disney, etc.

5) 5) Advocacy (Pembelaan)Advocacy (Pembelaan)- A Advocacy Web page contains contents that describe a A Advocacy Web page contains contents that describe a

cause, opinion or idea.cause, opinion or idea.- The purpose is to convince the reader of the validity of the The purpose is to convince the reader of the validity of the

cause, opinion or idea.cause, opinion or idea.- These web page usually present view of particular group or These web page usually present view of particular group or

association.association.- E.g : Democratic Party, The Society, Peace.E.g : Democratic Party, The Society, Peace.

6) 6) PersonalPersonal- A private individual who normally is not associated with A private individual who normally is not associated with

any organization often maintain a personal Web page.any organization often maintain a personal Web page.- People publish personal Web page for a variety of reason.People publish personal Web page for a variety of reason.- Other simply want to share life experiences with the Other simply want to share life experiences with the

world.world.

RELATIONSHIP BETWEEN LANRELATIONSHIP BETWEEN LAN Client/Server LANClient/Server LAN

– An architecture in which the user's PC (the client) is the An architecture in which the user's PC (the client) is the requesting machine and the server is the supplying machine, requesting machine and the server is the supplying machine, both of which are connected via a local area network (LAN) or both of which are connected via a local area network (LAN) or wide area network (WAN). Throughout the late 1980s and wide area network (WAN). Throughout the late 1980s and early 1990s, client/server was the hot buzzword as early 1990s, client/server was the hot buzzword as applications were migrated from centralized minicomputers applications were migrated from centralized minicomputers and mainframes to networks of desktop computersand mainframes to networks of desktop computers

– The ClientThe ClientThe client is the user's machine, which contains the user The client is the user's machine, which contains the user interface (Windows, Mac, etc.) and can perform some or all of interface (Windows, Mac, etc.) and can perform some or all of the application processing.the application processing.

– Specific Types of servers include: Specific Types of servers include: application serversapplication servers, , file serversfile servers, , terminal serversterminal servers, and , and mail serversmail servers. .

RELATIONSHIP BETWEEN LANRELATIONSHIP BETWEEN LAN

True Client/ServerTrue Client/ServerTo be a true client/server environment, both To be a true client/server environment, both client and server must share in the business client and server must share in the business processing. For example, a database server processing. For example, a database server processes requests from the client to look processes requests from the client to look up data or update data in its database. In up data or update data in its database. In this case, the server is performing a search this case, the server is performing a search at its end to respond to the query received at its end to respond to the query received from a client. It is not acting as a remote from a client. It is not acting as a remote disk drive; it is fully participating in the disk drive; it is fully participating in the transaction. To illustrate this concept, transaction. To illustrate this concept, review the examples below.review the examples below.

RELATIONSHIP BETWEEN LANRELATIONSHIP BETWEEN LAN

• Characteristics of a server:Characteristics of a server:– Passive (Passive (slaveslave) ) – Waits for requests Waits for requests – Upon receipt of requests, processes them Upon receipt of requests, processes them

and then serves replies and then serves replies

• Characteristics of a client:Characteristics of a client:– Active (master) Active (master) – Sends requests Sends requests – Waits for and receives server replies Waits for and receives server replies

1.1.2 1.1.2 WEB BROWSERWEB BROWSER

WEB BROWSERWEB BROWSER Definiton :Definiton :

A A Web BrowserWeb Browser is a is a software applicationsoftware application that enables a user to that enables a user to display and interact with text, images, and other information typically display and interact with text, images, and other information typically located on a located on a web pageweb page at a at a websitewebsite on the on the World Wide WebWorld Wide Web or a local or a local area network. area network. Text and images on a web page can contain hyperlinks to other web Text and images on a web page can contain hyperlinks to other web

pages at the same or different website. Web browsers allow a user to pages at the same or different website. Web browsers allow a user to quickly and easily access information provided on many web pages at quickly and easily access information provided on many web pages at many websites by traversing these links. Web browsers format HTML many websites by traversing these links. Web browsers format HTML information for display, so the appearance of a web page may differ information for display, so the appearance of a web page may differ between browsers.between browsers.

The program that serves as your front end to the Web on the The program that serves as your front end to the Web on the Internet. In order to view a site, you type its address (URL) into the Internet. In order to view a site, you type its address (URL) into the browser's Location field; for example, browser's Location field; for example, www.computerlanguage.comwww.computerlanguage.com, and the home page of that site is , and the home page of that site is downloaded to you. downloaded to you.

The home page is an index to other pages on that site that you can jump The home page is an index to other pages on that site that you can jump to by clicking an underlined hyperlink or an icon. Links on that site may to by clicking an underlined hyperlink or an icon. Links on that site may take you to other related sites.take you to other related sites.

• conts…conts… The two more popular browsers in use today are The two more popular browsers in use today are

Microsoft Internet ExplorerMicrosoft Internet Explorer, , Netscape Navigator Netscape Navigator and Mozilla firefoxand Mozilla firefox

Browser provide a variety of features, including the Browser provide a variety of features, including the capability to locate Web pages, to move forward and capability to locate Web pages, to move forward and backward between Web pages, to bookmark favorite backward between Web pages, to bookmark favorite Web pages, and to choose security settings. Web pages, and to choose security settings.

To locate a Web page using a browser, you type its To locate a Web page using a browser, you type its Uniform Resource Locator (URL) in the browser’s Uniform Resource Locator (URL) in the browser’s Address, or Location, bar.Address, or Location, bar.

A A Uniform Resource Locator (URL)Uniform Resource Locator (URL) is the address is the address of a document or other file accessible on the of a document or other file accessible on the internet.internet.

An example on the web is :An example on the web is : http://www.scsite.com/html3e/index.htmhttp://www.scsite.com/html3e/index.htm

protocol domain name pathprotocol domain name path The URL indicates to the browser to use the Hypertext Transfer Protocol (http) to The URL indicates to the browser to use the Hypertext Transfer Protocol (http) to

locate a Web page name locate a Web page name index.htmindex.htm in the in the html3ehtml3e folder on a Web server named folder on a Web server named scsite.comscsite.com

1.1.3 1.1.3 Two major browser :Microsoft Internet Explorer andTwo major browser :Microsoft Internet Explorer and Netscape NavigatorNetscape Navigator

Microsoft Internet ExplorerMicrosoft Internet Explorer

Microsoft Internet ExplorerMicrosoft Internet Explorer Microsoft's Web browser, which comes with Windows Microsoft's Web browser, which comes with Windows

starting with Windows 98. Commonly called "IE," versions starting with Windows 98. Commonly called "IE," versions for Mac and Unix are also available. Internet Explorer is for Mac and Unix are also available. Internet Explorer is the most widely used Web browser on the market. It has the most widely used Web browser on the market. It has also been the browser engine in AOL's Internet access also been the browser engine in AOL's Internet access software.software.

The Browser WarsThe Browser Wars- In the mid-1990s, Netscape began to turn the computer - In the mid-1990s, Netscape began to turn the computer world upside down with its Navigator browser, which was world upside down with its Navigator browser, which was a purchased product. Recognizing the Internet's potential, a purchased product. Recognizing the Internet's potential, Microsoft developed IE for Windows and gave it away. Microsoft developed IE for Windows and gave it away. Netscape eventually made Navigator free, and for a while, Netscape eventually made Navigator free, and for a while, IE and Navigator vied for top place by adding functions IE and Navigator vied for top place by adding functions fast and furiously. Ultimately, IE won the lion's share of fast and furiously. Ultimately, IE won the lion's share of the market because it was part of the operating system. the market because it was part of the operating system.

NetscapeNetscape

NetscapeNetscape (Netscape Communications Corporation, Mountain View, CA, (Netscape Communications Corporation, Mountain View, CA,

www.netscape.com) Part of America Online (AOL), Netscape www.netscape.com) Part of America Online (AOL), Netscape specializes in Web software, including the Netscape Web specializes in Web software, including the Netscape Web browser. Founded in 1994 by James Clark, former patriarch browser. Founded in 1994 by James Clark, former patriarch of SGI, and Marc Andreessen, who, along with Eric Bina, of SGI, and Marc Andreessen, who, along with Eric Bina, created the Mosaic browser at the University of Illinois, created the Mosaic browser at the University of Illinois, Netscape quickly became the number one topic of Netscape quickly became the number one topic of conversation as Internet and Web fever enveloped the conversation as Internet and Web fever enveloped the nation in the mid-1990s. nation in the mid-1990s.

The Netscape browser was one of the main issues in the The Netscape browser was one of the main issues in the Microsoft antitrust trial, during which Netscape was acquired Microsoft antitrust trial, during which Netscape was acquired by AOL by AOL

A Web browser from Netscape. In 2005, a beta of Version A Web browser from Netscape. In 2005, a beta of Version 8.0 was introduced for Windows with a Web site rating 8.0 was introduced for Windows with a Web site rating system that warns users if a site is suspicious. For system that warns users if a site is suspicious. For trustworthy sites, it renders pages using Internet Explorer trustworthy sites, it renders pages using Internet Explorer technology, but for dubious sites, pages are rendered as in technology, but for dubious sites, pages are rendered as in Firefox.Firefox.

1.1.4 1.1.4 Others Browsers Others Browsers a)a) Internet Explorer in MacintoshInternet Explorer in Macintoshb)b) American Online browsersAmerican Online browsers

- - (A division of Time Warner, Inc., Dulles, VA, www.aol.com) (A division of Time Warner, Inc., Dulles, VA, www.aol.com) The world's largest online information service with access to The world's largest online information service with access to the Internet, e-mail, chat rooms and a variety of databases the Internet, e-mail, chat rooms and a variety of databases and services. When dial-up was king, AOL had more than 30 and services. When dial-up was king, AOL had more than 30 million subscribers worldwide, but the number declined million subscribers worldwide, but the number declined significantly after the turn of the century as broadband cable significantly after the turn of the century as broadband cable and DSL took hold.and DSL took hold.

c)c) Web TVWeb TV - - The first Internet TV service that obtained widespread The first Internet TV service that obtained widespread

distribution of its set-top boxes in the retail channel. distribution of its set-top boxes in the retail channel. Developed in 1996 by WebTV and acquired by Microsoft in Developed in 1996 by WebTV and acquired by Microsoft in 1997, MSN TV uses an analog modem and telephone line to 1997, MSN TV uses an analog modem and telephone line to deliver the Web and e-mail to the TV set. In 2004, MSN TV 2 deliver the Web and e-mail to the TV set. In 2004, MSN TV 2 debuted for high-speed Internet users and provides audio and debuted for high-speed Internet users and provides audio and video streaming from the users's PC or the Internet to the TV. video streaming from the users's PC or the Internet to the TV. For information, visit www.msntv.com. Eg: Internet TV and For information, visit www.msntv.com. Eg: Internet TV and AOLTV.AOLTV.

Conts….Conts….d) d) OperaOpera

- - ((OPERAOPERA) () (OOpen pen PPLC LC EEuropean uropean RResearch esearch AAlliance) lliance) - - A Web browser for Windows, Mac and Linux from Opera Software, A Web browser for Windows, Mac and Linux from Opera Software,

Oslo, Norway (www.opera.com). Developed at Telenor (Norwegian Oslo, Norway (www.opera.com). Developed at Telenor (Norwegian Telecom) in 1994 and commercialized by Opera in 1995, it is noted for Telecom) in 1994 and commercialized by Opera in 1995, it is noted for its fast rendering of Web pages. Opera was the first browser to offer a its fast rendering of Web pages. Opera was the first browser to offer a host of unique features such as enlarging text and graphic elements on host of unique features such as enlarging text and graphic elements on the page and displaying multiple windows with only one instance of the the page and displaying multiple windows with only one instance of the program running. Having both paid and ad-supported versions, in late program running. Having both paid and ad-supported versions, in late 2005, the paid version was also made free.2005, the paid version was also made free.

- - For Cellphones and PDAs For Cellphones and PDAs Opera Mobile and Opera Mini are Opera Mobile and Opera Mini are versions for cellphones and PDAs. The Opera Platform is for developers versions for cellphones and PDAs. The Opera Platform is for developers who want to offer advanced Web applications on mobile phones.who want to offer advanced Web applications on mobile phones.

e) Lynxe) Lynx - A text-based Web browser created at the University of Kansas. - A text-based Web browser created at the University of Kansas. Though largely supplanted by graphical browsers such as Netscape Though largely supplanted by graphical browsers such as Netscape Navigator and Internet Explorer, Lynx is still popular among people Navigator and Internet Explorer, Lynx is still popular among people with visual disabilities and those with very slow modem connections. with visual disabilities and those with very slow modem connections. Example in Linux. Example in Linux.