Mac OS X 10.1 Server 10 CAL is the powerful internet and workgroup server. This retail box has a 10 Clients licenses pack, which allows up to ten users. This software combines the proven strength of UNIX with the famed Macintosh ease of use- all for one great price. Based on a new Apple core operating system, Mac OS X server delivers higher performance and greater reliability, making it the ideal environment for the Internet, publishing, and education. Part number M8583Z/A.