Facebook takes the open-source approach to its datacentres-- giving developers full access to to its computing power in its bid to compete against someone far wealthier-- Google.
The open-source datacentre project is OpenCompute, and for the moment allows interested parties access to any detail they desire-- from techn specs to chassis and motherboard CAD drawings. Facebook says this way the open-source developer community (alongside other partners) will help with further data center design and improvement.
In contrast, Google's servers are a mystery shrouded in secrets, where one doesn't even know whether the company's preference lies within Intel or AMD.
Of course, the OpenCompute project is not simply Facebook being generous-- with its building its own servers, Facebook finds itself in competition with Google-- and needs to run such servers as efficiently as possible, in order to keep users connected (and viewing ads).
With the social network lacking the search giant's resources, going open-source sounds like pretty sensible-- helping to shrink Google's advantage somewhat.