2. echo, Comments & Script Structure¶

What & why¶

echo is how a script talks to you, and it has more edge cases than any command this simple deserves. This lesson covers printing text cleanly, the two comment styles, and the handful of commands that give a script a readable shape.

`echo` basics¶

@echo off
echo Simple text.
echo Numbers 1 2 3 and symbols # $ %% are fine.

Note %% — a literal percent sign in a script is written %%. A single % starts variable expansion.

Print a blank line¶

echo.

No space before the dot. echo (with a trailing space and nothing else) prints ECHO is off. instead — a classic surprise. echo., echo:, echo( all print an empty line; echo( is the most robust.

`echo on` / `echo off` / bare `echo`¶

echo            &rem prints whether echo is on or off
echo on         &rem turn command-echoing back on (for debugging)
echo off        &rem turn it off again

Characters that need escaping¶

The shell metacharacters & | < > ^ ( ) must be escaped with a caret ^ when you want them printed literally:

echo Tom ^& Jerry
echo Use a pipe like this: ^|
echo 3 ^> 2 is true

Inside double quotes on an echo line the quotes are printed too, so quoting is not the way to escape here — use ^.

Comments¶

rem This is the official comment command.
:: This is a label that can never be jumped to, used as a comment.

:: is a trick: it's a broken label, and cmd skips it. It's faster to type and visually cleaner, but has two hazards:

Inside a for loop or a parenthesised block, :: can cause errors. Use rem there.
:: on the same line as code doesn't work as a trailing comment. Use &rem:

copy a.txt b.txt   &rem trailing comment, note the single &

Giving a script structure¶

@echo off
setlocal
title Deploy Tool
color 0A

cls
echo ============================
echo   Deploy Tool  v1.0
echo ============================
echo.

echo Step 1: checking prerequisites...
echo Step 2: copying files...
echo.

echo Done.
endlocal
pause

Command	Purpose
`title Deploy Tool`	Sets the window title bar.
`color 0A`	Background 0 (black), text A (bright green). `color` with no args resets.
`cls`	Clears the screen.
`setlocal` / `endlocal`	Isolates variable changes to this script — Intermediate Lesson 5. Get in the habit now.

Multi-line output¶

Every echo is its own line. For a block, either repeat echo, or use one redirect:

(
  echo Line 1
  echo Line 2
  echo Line 3
) 

rem Or build a here-doc-ish file:
(
  echo [settings]
  echo verbose=1
) > config.ini

Common mistakes¶

echo. with a space (echo .) prints a literal dot. No space.
echo %PATH% truncating — it doesn't truncate, but if PATH contains ) inside a parenthesised block it breaks parsing. Quote or restructure.
:: inside for ( … ) producing The system cannot find the drive specified. Use rem.
Unescaped & in an echo — echo Ben & Jerry runs Jerry as a command.
Trailing spaces after a value you echo into a file — they're included. Watch line ends.

Exercises¶

Print this exact block using echo, including the blank line:
```
Report

Status: OK
```
Print the literal string A & B | C > D on one line.
Write a script that sets the window title to Backup, clears the screen, prints a 3-line banner, then pauses.
Write notes.bat with a rem header comment describing what it does, three :: comments between sections, and one &rem trailing comment. Run it with @echo off removed and confirm no comment lines execute.
Make echo print 100% correctly (hint: %%).

Recap¶

echo text prints; echo. (no space) or echo( prints a blank line.
Literal % is %%; escape & | < > ^ ( ) with ^.
rem is the safe comment; :: is cleaner but avoid it inside for/blocks.
title, color, cls, setlocal/endlocal give a script shape.

Next: Variables & set →