I think a brief introduction is in order here:
DNS, or Domain Name System, is the service that converts a website's URL into its actual numerical address. In other words, when you type in "google.com", you are actually going to "18.104.22.168". Because that is to hard to remember, DNS servers around the world convert a site's URL into its actual numerical address for us. Think of it like a phone book: we don't look up numbers, we look up the names of people. When untouched, most people's computers are configured to use your ISP's DNS. But ISP's DNSs are actually quite slow in doing those conversions. While we are talking about fractions of seconds here, they are actually quite noticeable compared to a better DNS: OpenDNS.
It's actually quite simple to configure on your computer. Just follow these directions. A few clicks and numbers later and you'll have a far faster DNS set up for your computer. And if the internet seems a bit faster after the switch, that's because it is.
OpenDNS is the sort of thing that everybody should be using, but for one reason or another, is just not publicized enough. Being a geek, you may well have heard about it before. But if you hadn't, it's absolutely one of the web's best kept secrets.
As it happens, David Pogue actually did a video about OpenDNS about a year ago for the NYTimes and CNBC. As it also happens, I was in it. It was one of the coolest days of my life. Watch the video and learn everything you need to know about OpenDNS.