Autoexec.bat

Short for automatically executed batch file, the autoexec.bat is used in MS-DOS and early versions of Microsoft Windows operating systems (Windows 3.x and Windows 95) that holds and runs other programs that are listed in the file. 

For example, c:\windows\win is used to run Windows 3.x automatically each time the computer boots. For additional information and help with configuring and editing this file see our Autoexec.bat / Config.sys page.

Also see: Config.sys, Operating system definitions