A proxy server handles network connections on behalf of other computers. It either stands in for the client (the requester) or the server (responder) in a network transaction. An HTTP proxy is a category of network setting that can be configured in network (or Internet) accessing applications.
A web browser is an example of the type of application that can be configured to use a proxy server. Once the network settings of the browser have been set up, the browser will send all traffic to the named proxy server. Whenever the user types in an address in the address bar at the top of the browser, the web browser will contact the proxy server instead of the named address. The address the user wishes to access is instead given to the proxy server. The proxy visits that site on the client's behalf. This prevents any direct connection between the client and the server. The proxy fetches the required web page as though it were the originator of the request. It delivers the page to the client as though it were the web server. Most network-accessing applications have the ability to use different proxy servers for different types of requests. The HTTP proxy setting is one of these options.
HTTP stands for the Hypertext Transfer Protocol. All requests to web pages are carried by the HTTP protocol by default. Users can see what protocol is being used to reach a particular address by looking at the address bar. The “http://” code is the most frequently seen in this location. When the user populates an HTTP proxy settings in the browser's network options, all traffic that would show “http://” at the beginning on the web page's address will be sent to the specified proxy rather than directly to the site of the address.
The proxy settings screen is usually found under the network options from the Options sub-menu of the Tools menu in a browser. Some applications show only one proxy field initially, but make further fields available on and “Advanced Settings” screen. The HTTP proxy is usually the default or, at least, the first in the list. The full HTTP proxy setting requires two fields to be filled in: the proxy server's IP address and the recommended Port Number to access on that proxy.
Where other proxy types are available they will be FTP (for addresses beginning with "ftp://"), SOCKS ( a specific type of proxy server) and Secure/HTTPS (for addresses beginning with "https://"). Most network-accessing applications also allow exceptions to be set. This is a list of web addresses that will contacted directly and not through the specified proxy.