Importance of World Wide Web
What is the World Wide Web?
World Wide Web (WWW) is an architectural framework for providing distributed client-server service to access information spread at different locations that are called Websites all over the world. The WWW project was initiated by Tim Berners-Lee (CERN) in 1994. It consists of a large collection of documents is called WEB Pages. Each page may contain text, image, sound, video or any other form of media. Pages are viewed by the user with the help of a program called Browser.
Example: Internet Explorer, Mozilla Firefox, Google Chrome are this type of browsers.
Benefits of World Wide Web:
i. Connectivity, communication, and sharing.
ii. You will be able to access it from anywhere any place.
iii. You can learn anything for educational purposes.
iv. You can work from home and have access to a global workforce.
v. Buy, Selling and making money is very easy here.
vi. Banking, bills, Shopping and Entertainment.
Explain Hyperlink and Hypertext:
When a web page is displayed by this browser any part of it may have a link to any document anywhere around the world, that portion of the document has already been linked with another web page of a particular website with the use of a pointer. This type of link is known as Hyperlink and text associated with the hyperlink is known as Hypertext.
The document may contain a picture, image and sound also, which is called Hypermedia.
Web Accessibility Guidelines:
The user lies on the client-side and traverses through the websites. Every triggering action of the user is interpreted by the browser and the corresponding action is taken place by it. When a user clicks a hypertext, the web page pointed by the hyperlink is requested by the browser by sending the URL of the web page. The server lies in other parts of the world. On getting a request from a browser sends the reply. the reply may contain text or any other type of media. On getting this reply the browser again interprets it and displays it on the screen.
When a user clicks a hyperlink the browser performs a series of actions to fetch the web page pointed to. Let us consider that the user is trying to fetch the home page of MIT (Massachusetts Institute of Technology) The steps that are performed by the browser are given below:
1. The browser retrieves the URL related to the hyperlink clicked by the user.
2. The browser sends a request to the DNS server for getting the IP address of www.mit.edu/
3. The DNS server replies to the IP address 192.168.10.5
4. The browser makes a TCP connection to port number 80 of 192.168.10.5
5. The browser sends a request to the webserver (192.168.10.5)
6. The web server www.mit.edu/ sends an acknowledgement.
7. The TCP connection is released.
8. The browser displays the MIT (Massachusetts Institute of Technology) home page.
The server gets the file name from the client or the browser. It gives a reply to the client after getting the result. The server performs the following actions:
1. Accepts TCP connection from the browser or client.
2. Retrieves the name of the file as requested by the browser.
3. Searches for the file from the disk.
4. If the file is found, then it sends an error message to the client.
5. If the file isn’t found, then it sends an error message to the client.
6. It releases the TCP connection.