A Web application is a process that exists in on a Web server, which any Internet web user can have right to use over the internet. It contains three layers. The first layer would be a browser itself, the second would be a content making tools for example Java scripts or Active Server Pages, and lastly would be the web site’s database.
First in this, the Web browser creates the first demand to the second level, then, it will demand to the database to execute the requested task; it may be fetching the information from the database or updating the information.
Since Web site contents exist in on a web server, can be customized at any time - this is the main reason for online Web applications developed today by most of the associations.
For examples it includes login pages, dynamic content, shopping carts, wordpres and blogs and discussion boards as forum.