DNS (Domain Name System) servers translate human-readable URLs to their IP addresses. This means that you do not have to remember cryptic IP strings like 60.5.88.101 to get to a site.
While the default nameservers used by everyone do a good job, OpenDNS can do a better job. OpenDNS is a free service that replaces the default nameservers, and adds a few features into the mix.
Features include cached DNS lookups (for faster response), content filtering, domain blocking, phishing protection, porn blocking, statistics, shortcuts and error correction (so that entering wordpress.og takes you to wordpress.org). There have also been cases of default DNS servers having security loopholes (affecting most people), while OpenDNS had no such vulnerabilities.
OpenDNS has a community area, where you can read tutorials, forums, vote for new features etc.
Set up OpenDNS
Go to OpenDNS, and click on the ‘Computer’ option if you use a single computer and want to setup for it. If you have a router and use multiple computers, click ‘Router’.
Follow the instructions on enabling OpenDNS that come up(available for Windows, Ubuntu/SUSE, Mac OS X and even Nintendo Wii).
Once Open DNS is enabled, you can signup for a new account. Click on “Dashboard” link on top to get started with configurations. The dashboard looks like this:
Note: Opening an account is not required to use OpenDNS, but your settings and statistics will not work if you do not have an account.
Adding a network
The first thing you would want to do is add a network. If you use a single computer, enter the current IP address (which you can see on top right corner of the website).
Creating shortcuts to save time
You can configure any number of shortcuts from the dashboard. Click on the “Shortcuts” link. Add a short and easy shortcut and corresponding URL. In the screenshot above, you can see a few shortcuts that I set up.
IP setup
Most internet connections are dynamic in nature, meaning that it changes IP address every time you restart your computer or modem. This can cause problems for OpenDNS. To solve it, go to Settings -> Advanced Settings and check “Dynamic IP update”. For more details, see the support article on dynamic IP.
Note that checking the dynamic IP option is not required to use OpenDNS, but your settings and statistics will be skewed if you do not check it.
Content filtering
Content filtering is one of the more valuable settings on offer. Instead of relying on clumsy old software to block unwanted content, you can do so with OpenDNS. Click on Settings from dashboard, choose the filtering level and hit “Apply”. You can also block specific URLs, say facebook.com if your teenage son/daughter spends too much time on Facebook 
Today’s teenagers are tech-savvy and can easily disable most content-monitoring software (or even remove it via registry hacks), but cracking OpenDNS filtering is a lot harder.
Note: Content filtering may block some BitTorrent sites, so you may want to add BitTorrent sites you use to the whitelist of allowed sites.
The only problem with OpenDNS is that it is slower for some users. You should test it for a few days before taking the plunge (as I did). Have you used OpenDNS, and if so, how have your experiences with it been? Also, do you have any tips to use OpenDNS (features) more efficiently? Share them with us in comments.