Facebook, Amazon, and Google are all very picky about their server hardware, and these tech giants mostly build it themselves from commodity components. Frank Frankovsky, VP of hardware design and supply chain operations at Facebook, was instrumental in launching the Open Compute Project because he saw the waste in big cloud players reinventing things they could share. Frankovsky felt that bringing the open-source approach Facebook has followed for software to the hardware side could save the company and others millions—both in direct hardware costs and in maintenance and power costs.

via How Facebook threatens HP, Cisco, and more with its “vanity free” servers | Ars Technica.

The OCP hardware designs are “open” at a higher level. This way anyone can use standards-based components to create the motherboards, the chassis, the rack-mountings, the racks, and the other components that make up servers.