1. E-commerce | WWW World Wide Web - Concepts

2. World Wide Web (WWW) Tim Berners-Lee, a British computer scientist and former CERN  employee,  is the inventor of the Web.
The World Wide Web (www, W3) is an information system of interlinked hypertext documents that are accessed via the Internet.
It has also commonly known simply as the Web.
Individual document pages on the World Wide Web are called web pages and are accessed with a application software running on the user's computer, commonly called a web browser.
Web pages may contain text, images, videos, and other multimedia components, as well as web navigation features consisting of hyperlinks.

3. Hypertext & Anchor
Hypertext is text which contains links to other Text or Hyper Media (it can include graphics, video and sound etc). 
Anchor used for Jump To Specific Location On A same web Page.

4. Web Server, Web Server Software & Web Client
Web servers are computers that deliver (serves up) Web pages.
Every Web server has an IP address and possibly a domain name.
For example, if you enter the URL in your browser, this sends a request to the Web server whose domain name is hcc.edu.pk.
Web Server Software - Any computer can be turned into a Web server by installing server software such as Apache (for Linux O/S) . Web Server Software hold webpages and related data.
The client, or user, side of the Web. It typically refers to the Web browser in the user's machine.

5. Web Browser & Search Engine
A web browser (commonly referred to as a browser) is a software application for retrieving, presenting and traversing information resources on the World Wide Web.
An information resource may be a web page, image, video or other piece of content.
Search Engine a program that searches for and identifies items in a website databases that correspond to keywords or characters specified by the user, used especially for finding particular sites on the World Wide Web.
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6. HTTP: Hyper Text Transfer Protocol
HTTP (Hypertext Transfer Protocol) is the set of rules for transferring files (text, graphic images, sound, video, and other multimedia files) on the World Wide Web.
HTTP - provides a standard for Web browsers and servers to communicate.
Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

7. IP: Internet Protocol
Each computer (known as a host) on the Internet has at least one IP address that uniquely identifies it from all other computers on the Internet.
An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication.
Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

8. URL: Uniform Resource Locator
it is the global address of documents and other resources on the World Wide Web.
The first part of the URL is called a protocol identifier and it indicates what protocol to use, and the second part is called a resource name and it specifies the IP address or the domain name where the resource is located.
The protocol identifier and the resource name are separated by a colon and two forward slashes.
For Exampleftp://
Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

9. DNS (Domain Name System)
The domain name system (DNS) is the way that Internet domain names are located and translated into Internet Protocol addresses.
A domain name is a meaningful and easy-to-remember "handle" for an Internet address.
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10. Proxy Server
A proxy server is computer that functions as an intermediary between a web browser (such as Internet Explorer) and the Internet. 
Proxy servers help improve web performance by storing (cache) a copy of frequently used webpages.
Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

11. By Pass a Proxy Server using a Proxy Software
Why would I need a Proxy Server? There are many possible uses of proxy servers. One of them is: Anonymity: With some proxy servers, you can surf internet anonymously. Unrestricted surfing: Companies sometimes block part of internet. With a proxy server, you can surf blocked sites. Speed: Some proxies have web caching enabled. This means, that when a proxy transfers a web page, it remembers it. The next time you request the same page, the proxy will serve you from it's own memory instead of requesting that page again.
Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall

12. Markup Languages
Markup languages are designed for the processing, definition and presentation of text. 
HTML is a an example of a widely known and used markup language.
Copyright © 2014 Pearson Education, Inc. Publishing as Prentice Hall