Facebook made a major announcement today — a bit nerdier, perhaps, then what was expected — sharing its data center and and server designs with the world.

For about year, Facebook has been designing it own servers at its data center in Prineville, Ore. Today, the company’s CEO Mark Zuckerberg announced the Open Compute Project, which makes the designs open source. Zuckerberg said that Facebook wants to help foster the start-up ecosystem and make it more cost-effective to operate social networks.

“What we found over time was that what a lot of the stuff that the mass manufacturers were putting out wasn’t exactly in line with we needed and what other social apps needed. So we’ve geared this stuff to be more and more custom for building social apps,” Zuckerberg said.

The goal was to create the most efficient compute at the lowest price possible, said Facebook’s VP of technical operations, Jonathan Heiliger.

So the servers themselves are pretty barebones — no decorative plastic or paint here. The new servers run cool, light and cheap. They have larger heat sinks and fans, a way of supplying power that is extremely reliable and a cooling system powered by outside air.

“It’s really good for the environment and it’s a really smart use of our resources as a small and growing company.” Heiliger said.

Facebook is encouraging other hardware companies to follow suit and share their designs as well.

(Post Co. Chairman and Chief Executive Donald E. Graham sits on Facebook’s board of directors, and the newspaper and many Post staffers use Facebook for marketing purposes.)

Check out the company’s introductory video here: