REM is a command in the MS-DOS command interpreter frequently used in batch files. REM performs no action. The intent of this command is to supply remarks within the batch file that will be ignored by the computer, but visible to a programmer looking at the file. In effect, REM is batch language syntax for a comment. For example:
REM This line has no effect.
Any parameters to REM will be ignored. However, the exception to this rule is the
/? parameter, which, in modern versions of DOS, will display a summary of the command. Therefore, one should not attempt to indicate a comment beginning with
If REM is the first token on a line in DOS's CONFIG.SYS file, that line will be ignored. Therefore, REM also provides a commentary feature in that file. However, this functionality is only available since, I believe, DOS 5.0.