In computer networks, a proxy server is a server (a computer system or an application) that acts as an intermediary for requests from clients seeking resources from other servers. A client (you) connects to the proxy server, requesting some service, such as a file or website and the proxy server evaluates the request as a way to simplify and control its complexity. Today, most proxies are web proxies, facilitating access to content on the World Wide Web.
In simple words a proxy website or server helps you to access blocked website or content over Internet by bypassing normal way of accessing it.
Proxy websites are usually very simple to use, you just need to enter the website URL and have to hit go or browse button. Following are the list of some proxy websites, now you can browse website of your choice and Remember you don’t have to spend a single penny to use these proxy website or service.
Do proxy websites always help to access blocked content?
No! Because when someone limits Internet or network access he/she/they also make sure that they don’t let proxy websites accessible and they (computer admin/staff) usually block proxy websites too. In this situation when proxy websites are blocked you have to look for other ways to access blocked contents.
At an office where I was an intern I find Netgear firewall installed and the firewall was so poorly configured that nothing was accessible, even access to official website and email was restricted but in a few days I found some ways to access most of the online stuff.
Open google chrome and instead of putting website address put the keywords so that it will be searched in google and then click the search engine result page link to access that website.
The other way is that websites that support secure http can be accessed using https instead of http. To access facebook visit https://facebook.com instead of http://facebook.com.