Apple software that adds server functionality to any Mac running OS X. Starting with OS X Version 10.7 (Lion), OS X Server adds centralized management of desktop and mobile devices, file sharing, backup, calendars, mail, wikis and Xcode deployment. Introduced in 1999, Mac OS X Server was pre-installed on various Mac models that were sold as dedicated servers. As of OS X 10.7, the software became available from the Mac App Store for any Mac. See Mac OS X and Xserve.