21-11-2012, 01:11 PM
Introduction to the Internet and Web
Internet.ppt (Size: 144.5 KB / Downloads: 279)
Internet
It is the largest network in the world that connects hundreds of thousands of individual networks all over the world.
The popular term for the Internet is the “information highway”.
Rather than moving through geographical space, it moves your ideas and information through cyberspace – the space of electronic movement of ideas and information.
No one owns it
It has no formal management organization.
As it was originally developed by the Department of defense, this lack of centralization made it less vulnerable to wartime or terrorist attacks.
To access the Internet, an existing network need to pay a small registration fee and agree to certain standards based on the TCP/IP (Transmission Control Protocol/Internet Protocol) .
The uses of the Internet
Send e-mail messages.
Send (upload) or receive (down load) files between computers.
Participate in discussion groups, such as mailing lists and newsgroups.
Surfing the web.
What is Web?
The Web (World Wide Web) consists of information organized into Web pages containing text and graphic images.
It contains hypertext links, or highlighted keywords and images that lead to related information.
A collection of linked Web pages that has a common theme or focus is called a Web site.
The main page that all of the pages on a particular Web site are organized around and link back to is called the site’s home page.
How to access the Internet?
Many schools and businesses have direct access to the Internet using special high-speed communication lines and equipment.
Students and employees can access through the organization’s local area networks (LAN) or through their own personal computers.
Another way to access the Internet is through Internet Service Provider (ISP).
To access the Internet, an existing network need to pay a small registration fee and agree to certain standards based on the TCP/IP (Transmission Control Protocol/Internet Protocol) reference model.
Each organization pays for its own networks and its own telephone bills, but those costs usually exist independent of the internet.
The regional Internet companies route and forward all traffic, and the cost is still only that of a local telephone call.
Client/Server Structure of the Web
Web is a collection of files that reside on computers, called Web servers, that are located all over the world and are connected to each other through the Internet.
When you use your Internet connection to become part of the Web, your computer becomes a Web client in a worldwide client/server network.
A Web browser is the software that you run on your computer to make it work as a web client.
Hypertext Markup Language (HTML)
The public files on the web servers are ordinary text files, much like the files used by word-processing software.
To allow Web browser software to read them, the text must be formatted according to a generally accepted standard.
The standard used on the web is Hypertext markup language (HTML).
Addresses on the Web:IP Addressing
Each computer on the internet does have a unique identification number, called an IP (Internet Protocol) address.
The IP addressing system currently in use on the Internet uses a four-part number.
Each part of the address is a number ranging from 0 to 255, and each part is separated from the previous part by period,
For example, 106.29.242.17