Google has begun offering their own "free, global Domain Name System (DNS) resolution service, that you can use as an alternative to your current DNS provider."
What is a DNS? According to the experts at PC World: "In a nutshell, the DNS — or domain name system — is what actually finds and directs you to a Web site when you type in its URL." Basically, it's similar to how a phone number it attached to a certain person or an address locates a certain building.
Still unsure why you would want to use this new Google DNS system?
Think of it this way: Why use the U.S. Postal Service? Do you really want those gun-toting lunatics putting their paws all over your mail?
Of course not! Just give me your mail and I'll make sure it gets to where it needs to go. Instead of dropping off packages at your filthy "local post office," meet me down at Battery Park, hand your stuff over to me and I'll take it from there. No need to worry!
And if I occasionally eat the contents of your care packages or cash your rent checks into my bank account, so be it.
That, in a nutshell, is Google Public DNS.