There is various reasons to use proxy server, let go over some of the major reasons:
Hide your IP address.
Your IP Address can tell a lot about you, it can tell what is your country, your city and who is your Internet Service Provider. So if you don’t want the web site that you browse to will know your IP, you should use proxy server to browse.
Let see what we can tell about you:
Your City: (Unknown city)
Your IP: 38.107.179.240
Your Internet Provider: 107.179.240
Your OS: unknown
Your Browser: unknown
Browser Version:
If those details are correct then you need to use proxy server to hide your IP from any website. In the next image you can see how proxy server is changing your IP.

How proxy hide my IP address
Hide your computer details.
When you surf the net, you are sending details about your computer system to the website. In your request, your browser sending additional text that called ‘User-Agent’. Details such: your browser type and version, your Operating System, the language of the browser and more can be easily hide if you are using proxy.
Browse from another country
Some websites require from you to be in specific country to browse of get data from it. By changing your IP you can ‘change’ your browsing country. For example, you are not allow to watch Mad Man TV serial if you out side of U.S.A. ST Proxy swithcer offer you free list of proxy with different regions.
Download Wait Time
The big file sharing websites require wait time between each download. When you are using different proxy each time you download file the sharing website you will not need to wait because each time you download file using different details.

