$ simple use of the dollar sign $

[OOdle nOOdle]

i am trying to write to a new file (filename) using cat and i require to use a $ as this is in the previously written script, but when i was testing to try and get a similar/simpler file to work...it doesn't

here's what i have

cat > filename << EOD
#
#
1 2 3
anything
$hello
#
#
EOD

and i get "hello: undefined variable"

but surely, it is just writing to text so it shouldn't matter about the $ ?

please help

[devils casper]

$ sign is special character. prefix \ (backslash) to escape it.

cat > filename << EOD
#
#
1 2 3
anything
\$hello
#
#
EOD