The MVPS Hosts file contains the mappings of IP addresses to host names. You can use it to block ads, banners, cookies, web bugs, and even most hijackers. This is accomplished by blocking the Server that supplies these little gems. Example – the following entry 127.0.0.1 ad.doubleclick.net blocks all files supplied by the DoubleClick Server to the web page you are viewing. This also prevents the server from tracking your movements.
In many cases this can speed the loading of web pages by not having to wait for these ads, banners, hit counters, etc. to load. This also helps to protect your Privacy by blocking servers that track your viewing habits, known as “click-thru tracking”. Another feature of the HOSTS file is it’s ability to block other applications from connecting to the Internet, as long the the entry exists.