System Preferences is an application

Application software

Application software, also known as an application or an "app", is computer software designed to help the user to perform specific tasks. Examples include enterprise software, accounting software, office suites, graphics software and media players. Many application programs deal principally with...

 included with the Mac OS X

Mac OS X

Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...

 operating system that allows users to modify various system settings which are divided into separate preference pane

Preference Pane

A Preference Pane is a special dynamically loaded plugin in Mac OS X. Introduced in Mac OS X v10.0, the purpose of a Preference Pane is to allow the user to set preferences for a specific application or the system by means of a graphical user interface. Preference Panes are the OS X replacement to...

s. The System Preferences application was introduced in the first version of Mac OS X to replace the control panel

Control panel (Mac OS)

Under Mac OS 9 and earlier, a control panel is a small application which enabled the user to modify software and hardware settings such as the sound volume and desktop pattern. Control panels differ from extensions in that they allow the user to specify options, whereas extensions provide the user...

 that was included in previous versions of the Mac operating system

Mac OS

Mac OS is a series of graphical user interface-based operating systems developed by Apple Inc. for their Macintosh line of computer systems. The Macintosh user experience is credited with popularizing the graphical user interface...

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Before the release of Mac OS X in 2001, users modified system settings using control panels.