AutoPlay Feature in Windows
A computer with the Windows operating system includes plenty of features and options to enjoy browsing the Internet, communicate via email or other online services, play games, view media files and more. Windows can also play digital multimedia content from devices containing media (music, graphic and video) files. Examples of these devices include USB flash drives, CD or DVD drives, portable media players like iPods, and many others. Microsoft has enhanced the way Windows will handle such contents by adding an AutoPlay feature, also known as autorun, that automatically detects and reacts to new devices on a system.
Audio and video files in removable devices will automatically play if the computer is configured to use the AutoPlay feature when you insert media or connect devices. The files will use the default media player program to play the audio or video. If Autoplay has not been configured, Windows will display a pop-up question to ask the end-user what they would like to do. You've probably seen these type messages when you inserted a blank DVD-R or connected a digital camera.
Software developers also make use of Autoplay's ability to have programs run automatically via a file called Autorun.INF. If you insert a USB flash drive, CD or DVD that has the Autorun.INF file in the root folder, Windows will automatically run whatever executable file is defined in Autorun.INF.
These actions performed by the AutoPlay and autorun feature in Windows have helped in reducing support costs by software publishers by simplifying installation procedures for software and hardware, but there is a potential risk in using them.