Mac OS X Server
A server operating system version of the Mac OS X operating system for Apple computers. Mac OS X Server, also known simply as OS X Server, is available as a $19.99 add-on for the OS X Mountain Lion (v10.8) and Mavericks (v10.9) operating systems. The OS X Server add-on can be purchased through the Mac App Store.
Mac OS X Server adds specialized server features to the regular OS X operating system such as file sharing via the SMB2 protocol, mail and messages server capabilities, a Profile Manager for configuring and managing client Mac computers and iOS devices, an Xcode Server tool for software development, a caching server, backup server features for preserving data on client computers, a Wiki server for group collaboration and communication, and more.