Howto Quickly Write A Note Without A Text Editor

[Dougal]

If you want to quickly write a few lines to a file, without using mp or such other cli text editors... use a here document:
Just write:

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cat >myfile <<_END

then write whatever you want (including hitting enter) and when you're done just type _END...

For example:

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# cat >myfile <<_END
> bla
> meh
> _END
# cat myfile 
bla
meh
# 

[rcrsn51]

Or just

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cat > myfile

and press CTRL/D when done.

[Laie]

COOL

[laika]

Or just...

But then no orderly > at the beginning of each line Seriously, though, here files have some specific application, don't they?

[Dougal]

here files have some specific application, don't they?

They're a tool... you can do what you want with them.
One good usage is if you write a script and want to give a usage/help option, then rather than using echo and having to play with quoting (if your text includes quotes you'll need to escape them etc.), just write the text you want to output and enclose it in a here document.
Another place where they're is where you have a loop that reads from the output of a subshell:
If you pipe the subshell into the loop,

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grep 'bla' file | while read Line ; do
  #do something
done

then the loop is part of the subshell and any variables you set in it will not be remembered.
If the loop reads from a here document

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while read Line ; do
  #do something
done<<_END
$(grep 'bla' filename)
_END

then you're ok...