Per the official Google blog,

As people begin to use Google Public DNS, we plan to share what we learn with the broader web community and other DNS providers, to improve the browsing experience for Internet users globally. The goal of Google Public DNS is to benefit users worldwide while also helping the tens of thousands of DNS resolvers improve their services, ultimately making the web faster for everyone.

For those who have no inkling as to what a DNS is, head on to Domain Name System on Wikipedia. Domain Name System is like a telephone directory for the Internet. It helps in translating human-friendly computer hostnames into IP addresses. For example, www.some-domain-name-xyz.com translates to a similar IP like 208.77.188.166.

As with all other Google products, Google public DNS also focuses on mainly speed and security. Google claims that by using their DNS service, your browsing will be speedier and secure.  To start using Google public DNS, you will need to make changes to your TCP/IP properties and set preferred DNS server to any of the following:
IP: 8.8.8.8
IP: 8.8.4.4

In windows xp, go to Local Area connection properties under Network connections in control panel.  Select Internet Protocol (TCP/IP) and point the DNS servers to google’s DNS IP address above.

So, if your ISP’s DNS server is occassionally itchy, give you problems often or is a bit slow (though usually DNS hosted by the ISP are fastest for their network), you may want to switch to Google’s DNS offering. I have been using it since its launch along with OpenDNS and am quite satisfied with the speed.

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