Prior to OS X, Apple's Appleshare services provided server applications such as file and printer sharing and user management.
As of version 10.0 of the Mac OS, the server version and the standard version are nearly identical; OS X Server mainly adds server management software—web, mail, and user services. Most of OS X Server's services are based on standard BSD tools, e.g., the Apache web server; OS X Server adds a GUI interface to these services. An exception, however, are User services, which are based on (Next) NetInfo.
A partial list of updates to Mac OS X Server
See also: Mac OS.