The Mac OS is designed to run on a Motorola chip. This means the lowest level microcode used by the Mac is not the same as that designed for the Intel chip. The Macintosh, like Windows, is a complete operating system. These partners are aided by a series of other mini-applications which extend the functionality of the operating system or which give you, the user, a way to alter the way the machine works to your liking. You've encountered control panels with Windows.
Control panels are special pieces of software which the user can adjust.
For example, if you wanted to type in Japanese, you can add a simple set of extensions to the OS and the fonts you want. Nevertheless, problems can arise. One of the most useful tools is rebuilding the desktop . The desktop is a hidden database file that the operating system uses to locate files on the disk and to associate files with the correct application, similar to Windows' FAT and Registry combined. The desktop also holds comments about the files, the date of the creation and modification of the file, etc.