Mac OS X Lion is an operating system (OS) developed by Apple, Inc. As an operating system, Mac OS X Lion is responsible for the basic operation of your Mac computer and the programs that run on it.
Mac OS X Lion is the eighth major release of Mac OS X. The X refers to version 10 of the Mac operating system which was originally released in 2001 as Mac OS X Cheetah.
Apple has used big cat names to denote each Mac OS version since 10.0, with Lion representing Mac OS 10.7.
Programs or Applications Run on Mac OS
When you first launch Mac OS X, that is, boot up your computer, you will find that the Finder will be immediately available. The Finder is the default file manager used by Mac OS X, responsible for the Mac desktop experience.
Finder Makes It Possible for You to Interact with Mac OS
Finder is responsible for the look and feel of Mac OS X including all the icons, files, menus, the desktop, and windows. If you are familiar with Windows, think of Finder as the Explorer of Mac OS.
Simply put, Finder is the graphical user interface (GUI) of Mac OS.
In the following section we’ll boot up Mac OS X ad become familiar with the login process.