Lets frustrate your friend. Just try it once .

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1. open a notepad
2. Type the following code :
@ECHO off
:Begin
msg * Hi
msg * how are you?
msg * Are you having fun?
msg * I am!
msg * Lets have fun together!
msg * Because you have been o-w-n-e-d
GOTO BEGIN
3. Save it as pc.bat
4. Run it .