Use :: or REM

:: commenttttttttttt REM commenttttttttttt 

BUT (as people noted):

• if they are not in the beginning of line, then add & character:
  your commands here & :: commenttttttttttt
• Inside nested parts (IF/ELSE, FOR loops, etc...) :: should be followed with normal line, otherwise it gives error (use REM there).
• :: may also fail within setlocal ENABLEDELAYEDEXPANSION

No, plain old batch files use REM as a comment. ECHO is the command that prints something on the screen.

To "comment out" sections of the file you could use GOTO. An example of all these commands/techniques:

REM it starts here the section below can be safely erased once the file is customised ECHO Hey you need to edit this file before running it! Check the instructions inside ECHO Now press ctrl-c to interrupt execution or enter to continue PAUSE REM erase the section above once you have customised the file python executed1.py ECHO Skipping some stuff now GOTO End python skipped1.py python skipped2.py :END python executed2.py 

What can I say? batch files are a relic of times long gone, they're clunky and ugly.

You can read more on this website.

EDIT: modified the example a bit to have it contain the elements you are apparently looking for.

The :: instead of REM was preferably used in the days that computers weren't very fast. REM'ed line are read and then ingnored. ::'ed line are ignored all the way. This could speed up your code in "the old days". Further more after a REM you need a space, after :: you don't.

And as said in the first comment: you can add info to any line you feel the need to

SET DATETIME=%DTS:~0,8%-%DTS:~8,6% ::Makes YYYYMMDD-HHMMSS 

As for the skipping of parts. Putting REM in front of every line can be rather time consuming. As mentioned using GOTO to skip parts is an easy way to skip large pieces of code. Be sure to set a :LABEL at the point you want the code to continue.

SOME CODE GOTO LABEL ::REM OUT THIS LINE TO EXECUTE THE CODE BETWEEN THIS GOTO AND :LABEL SOME CODE TO SKIP . LAST LINE OF CODE TO SKIP :LABEL CODE TO EXECUTE 

Multi line comments

If there are large number of lines you want to comment out then it will be better if you can make multi line comments rather than commenting out every line.

See this post by Rob van der Woude on comment blocks:

The batch language doesn't have comment blocks, though there are ways to accomplish the effect.

GOTO EndComment1 This line is comment. And so is this line. And this one... :EndComment1 

You can use GOTO Label and :Label for making block comments.

Or, If the comment block appears at the end of the batch file, you can write EXIT at end of code and then any number of comments for your understanding.

@ECHO OFF REM Do something • • REM End of code; use GOTO:EOF instead of EXIT for Windows NT and later EXIT Start of comment block at end of batch file This line is comment. And so is this line. And this one... 

Putting comments on the same line with commands: use & :: comment

color C & :: set red font color echo IMPORTANT INFORMATION color & :: reset the color to default 

Explanation:

& separates two commands, so in this case color C is the first command and :: set red font color is the second one.

Important:

This statement with comment looks intuitively correct:

goto error1 :: handling the error 

but it is not a valid use of the comment. It works only because goto ignores all arguments past the first one. The proof is easy, this goto will not fail either:

goto error1 handling the error 

But similar attempt

color 17 :: grey on blue 

fails executing the command due to 4 arguments unknown to the color command: ::, grey, on, blue.

It will only work as:

color 17 & :: grey on blue 

So the ampersand is inevitable.

You can comment something out using :: or REM:

your commands here :: commenttttttttttt 

or

your commands here REM commenttttttttttt 

To do it on the same line as a command, you must add an ampersand:

your commands here & :: commenttttttttttt 

or

your commands here & REM commenttttttttttt 

Note:

• Using :: in nested logic (IF-ELSE, FOR loops, etc...) will cause an error. In those cases, use REM instead.

I prefer to use:

• REM for comments
• &REM for inline comments

Example:

@echo off set parameter1=%1% REM test if the parameter 1 was received if defined parameter1 echo The parameter 1 is %parameter1% &REM Display the parameter 

Commenting a line

For commenting line use REM or :: though :: might fail inside brackets

within delayed expansion lines starting with !<delimiter> will be ignored so this can be used for comments:

@echo off setlocal enableDelayedExpansion echo delayed expansion activated !;delayed expansion commented line echo end of the demonstration 

Comment at the end of line

For comments at the end of line you can again use rem and :: combined with &:

echo --- &:: comment (should not be the last line in the script) echo --- &rem comment 

Commenting at the end of file

As noting will be parsed after the exit command you can use it to put comments at the end of the file:

@echo off echo commands exit /b ------------------- commnts at the end of the file ------------------ 

Inline comments

Expansion of not existing variables is replaced with nothing ,and as setting a variable with = rather hard you can use this for inline comments:

@echo off echo long command %= this is a comment =% with an inline comment 

Multiline comments

For multiline comments GOTO (for outside brackets) and REM with conditional execution (for inside brackets) can be used. More details here:

@echo off echo starting script goto :end_comments comented line one more commented line :end_comments echo continue with the script ( echo demonstration off rem/||( lines with comments ) echo multiline comment inside echo brackets ) 

And the same technique beautified with macros:

@echo off ::GOTO comment macro set "[:=goto :]%%" ::brackets comment macros set "[=rem/||(" & set "]=)" ::testing echo not commented 1 %[:% multi line comment outside of brackets %:]% echo not commented 2 %[:% second multi line comment outside of brackets %:]% ::GOTO macro cannot be used inside for for %%a in (first second) do ( echo first not commented line of the %%a execution %[% multi line comment %]% echo second not commented line of the %%a execution ) 

This is an old topic and I'd like to add my understanding here to expand the knowledge of this interesting topic.

The key difference between REM and :: is:

REM is a command itself, while :: is NOT.

We can treat :: as a token that as soon as CMD parser encounters the first non-blank space in a line is this :: token, it will just skip the whole line and read next line. That's why REM should be followed by at least a blank space to be able to function as a comment for the line, while :: does not need any blank space behind it.

That REM is a command itself can be best understood from the following FOR syntax

The basic FOR syntax is as follows

FOR %v in (set) DO <Command> [command param] 

here <Command> can be any valid command So we can write the following valid command line as rem is a command

FOR %i in (1,2,3) DO rem echo %i 

However, we CANNOT write the following line as :: is not a command

FOR %i in (1,2,3) DO :: echo %i 

You can add comments to the end of a batch file with this syntax:

@echo off :: Start of code ... :: End of code (I am a comment So I am! This can be only at the end of batch files 

Just make sure you never use a closing parentheses.

Attributions: Leo Guttirez Ramirez on https://www.robvanderwoude.com/comments.php

You can use :: or rem for comments.

When commenting, use :: as it's 3 times faster. An example is shown here

Only if comments are in if, use rem, as the colons could make errors, because they are a label.