History of Mac OS

OS X

OS X ( /ˈoʊ ˌɛs ˈtɛn/) is the line of graphical operating systems developed, marketed, and sold by Apple Inc. which succeeded the original Mac OS, which had been Apple's primary operating system since 1984. Unlike the earlier Macintosh operating system, OS X is a Unix-based operating system built on technology developed at NeXT from the second half of the 1980s until early 1997, when Apple purchased the company.

The first version was OS X Server 1.0 in 1999, which retained the earlier Mac operating system's "platinum" appearance and even resembled OPENSTEP in places. The desktop-oriented version, OS X, followed in March 2001 supporting the new Aqua user interface. Since then, seven more distinct "end-user" and "server" versions have been released. In July 2011 OS X v10.7 was released with new features, such as Launch Pad, which is a springboard-style home for applications, similar to the iPad, iPod and iPhone; and Mission Control, an improved exposé. Releases of OS X are named after big cats. For example, Apple calls OS X v10.5 "Leopard", while its previous release was called "Tiger".

Versions of OS X: