Proxy servers work as an intermediary system between a browser and a server. Further, it requests on the behalf of the browser from the server.
From the figure-1 you can understand that process. Between the client (Browser) and server another server is placed which is the proxy server.
When the client request resource from the web server. The first request goes to the proxy server. Then the proxy server makes a request to the original web server. The original web server reply to the proxy server. Again proxy server reply to the client. This is the basic request-reply procedure in the proxy server environment.
The use of the proxy server is.
A proxy server can keep the most recently used web pages. And when a browser requests it again the proxy server will deliver the page faster than the original server. Hence, it speeds up
the request-reply procedure faster.
It is also useful to surf web as anonymously. Since all the requests come from the proxy server to the original web server.
The proxy server can enhance the security. Because when hackers try to access your data their request will first go at the proxy server.
Many universities use the proxy server to control Internet access. Students have to register for
the proxy. Then they will get the proxy username and password. When they access Internet the proxy server authenticates. If the user is authorized permission is granted to access.
Using the proxy server auditing can be accomplished. For instance, how much data a user can use.