A proxy server is a server that can be found between, for example, a client PC web browser and a real server. When the client application sends a request to the real server, the proxy server intercepts the request and tries to comply with it. If the proxy server cannot complete the request it is then forwarded to the real server.

As proxy servers fulfil requests, the results are stored in its cache, So, the next time a client sends the same requests, the result is taken from the proxy’s cache, dramatically reducing response time.

Another application for proxy servers is to filter requests. This way, companies can limit the sites that their employees can access online and the server can also provide additional security.

Lastly, online proxies are also used for anonymous surfing, hiding the user’s IP to prevent sites from retrieving personal information from web users.

Proxy servers are one of many types of servers, some of the most common types are:

Application servers - Application servers are used as connections between database servers and clients.

FTP servers – File Transfer Protocol servers are one of the most used servers on the internet for transferring files safely from one computer to another, providing security and control over the whole transfer process.

Mail servers - Used by companies to transfer and store e-mails on their corporate networks, either LAN or WAN, and over the internet.

Web servers – All static content is delivered over the internet via web servers. These servers retrieve information from disks and transfer it across the net to a user’s web browser through HTTP.

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