AutoRun is a feature of the Windows operating system that causes a certain file to open or a certain program to run automatically as soon as a compact disc (CD) is inserted into the CD drive. The action taken is determined by a file called AUTORUN.INF. If the file to be opened is a music or multimedia file, the feature is called AutoPlay.
If there is no AUTORUN.INF file on an enhanced CD containing data files as well as music or multimedia files, a computer with Windows will normally start playing the music or multimedia as soon as the CD is inserted. If there is an AUTORUN.INF file on the CD, the computer follows the instructions contained in it. It is possible to disable the AutoPlay feature for music or multimedia files, or to enable it if it has been previously disabled.