ver (command)

In computing, ver is a command in various DOS, OS/2 and Microsoft Windows command line interpreters (shells) such as COMMAND.COM, cmd.exe and 4DOS/4NT. It prints the name and version of the operating system or the command shell.

Some versions of MS-DOS support an undocumented /r switch, which will show the revision as well as the version. The command is also available in the open source MS-DOS emulator DOSBox.