Graphical user interface based operating system designed and developed by Apple is marketed as Mac OS. This is for the Macintosh line of computer systems. It used Hierarchical File System (HFS), which is advanced file system and had a true directory tree. Previous Mac operating systems were named in a regular number Mac OS 8 and Mac OS 9. After that Apple introduced tenth major release as name –Mac OS X. Mac OS X introduced many new features and functions to make it more stable. Apple released six version of Mac OS X till now. Mac OS X version named after big cats.

Following are the different Mac OS-

Mac OS X Cheetah- Mac OS X Cheetah was the first major release of Mac OS X, version 10.0 as desktop and server operating system. But it was not successful at that time.

Mac OS X Puma- Mac OS X Puma is the Mac OS X is version 10.1. It is the second major release of Mac OS X as desktop and server operating system. It was improved version than first one but somewhere it is lacking behind.

Mac OS X Jaguar- Mac OS X version 10.2, codename jaguar is the third major release of Mac OS X for desktop and server both. It introduced features and improved previous one.

Mac OS X Panther - Mac OS X panther (version 10.3) was the fourth major release of Apple’s desktop and server operating system. It updated older features and introduced more than 150 features.

Mac OS X Tiger- Mac OS X version 10.4, Tiger is the codename. Mac OS X Tiger is the fifth major released of Apple’s desktop and server OS for Macintosh computers. It was the longest running version of Mac OS X.

Mac OS X Leopard- Mac OS X Leopard is the sixth major release of Mac OS X. It is latest desktop and server operating system. It contains over 300 changes and enhancements over its predecessor- Mac OS X v10.4.

Xserve- Xserve is the Apple Inc.'s 1U rackmount line of server computers. It was the first designated server hardware. It is used for various applications like file server, web server or even high-performance computing applications using clustering.

Xserve RAID- Xserve RAID was a mass storage device design and developed from Apple. It offers massive redundant storage. It is enriched with massive features.

OSX server- OSX server is the UNIX server operating system which is based on the same architecture like Mac OS X. For managing and deploying servers, it is bundled with additional services, applications and administration tools.