IP means Internet Protocol which act as an identity of a your machine like your internet modem and your computer both have an IP address. You might have noticed that some websites are are inaccessible in your region because Govt. or website owner had blocked it in your area; blocking is done on the basis of IP and IP ranges so you can easily visit a blocked website using some proxy server because it hides your IP address and assigns you a random IP that you can use for browsing Internet.
There are many proxy website like zend2.com and hidemyass.com etc, we have also posted a tutorial on how you can easily create your own proxy website using WordPress. Now here is a list of a few good proxy extensions which you can use directly in your Google Chrome browser for hiding your identity or for accessing blocked website.