What is Google Public DNS?

Google Public DNS is a free, global Domain Name System (DNS) resolution service, that you can use as an alternative to your current DNS provider.
Got Confused…Ok let me explain this is in simple non technical terms (as far as I can). You use Internet right. So how do you access any website, by entering its domain name like www.beingpc.com in any of your favorite browser and hitting enter. But the inside story is different.
When you try to access any webpage in our case www.beingpc.com your computer resolves this domain name (website URL) into IP Address with the help of the Domain Name Server. By default, Windows uses your ISP’s DNS server.
So in short, to open a website Windows need to resolve the domain name to IP Address by looking it in Domain Server provided by your ISP. So the faster your PC resolve the faster you get connected. So this is where Google Public DNS helps, it helps you resolves the domain names into IP Address faster than other.
More Detailed Explanation
Performance comparison of OpenDNS and Google DNS

Setup Google DNS on your Computer
If you would like to setup Google DNS on your Computer than follow the steps below:
Go to Start > Control Panel
Select Network And Internet > Network & Sharing Center
In the left pane click on Change Adapter Settings
Right Click on Local Area Connections and select properties

Adapter setting

Select Internet Protocol Version 4 and click on Properties

Now set the Ip Addresses as below

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