Internet is the spine of this modern age and I know that no one would contradict this statement. And it is equally important for us to stay fast and safe on Internet. So Google came up with their Public DNS to serve the purpose.
Public Google DNS is a new free service from Google that name resolution can be used as an alternative to your DNS servers to increase the speed of navigation with an eye on security.
You can use it immediately, to set your computer or router to use Google Public DNS Please follow these instructions
which includes instructions for Windows, Mac, Linux and your router
If you decide to try the Google Public DNS, your browser will use them to do all the DNS Lookups.
Note: The DNS protocol is very important infrastructure web. Each time you visit a website, your computer makes a DNS Lookup. Complex Web pages require several DNS Lookups before you start loading the page itself, then to have very fast DNS servers (like Google), also helps speed up navigation.