bash has 3 kinds of quotes

‘single quotes’

$ echo '$HOME\n' 
$HOME \n

“double quotes”

$ echo "$HOME \n" 
/home/bork\n

(only double quotes expand variables)

$’

$ echo $'$HOME\n' 
$HOME

(invisible newline)
(only $' expands escape sequences like \n or \')

you can quote multiline strings

$ MESSAGE="Usage:

here's an explanation of how to use this script!"

here documents

heredocs are a way to write string containing quotes:

expands variables:

$ cat <<PANDA  
he said: 
"that's $5"
PANDA

doesn’t expand:

$ cat <<'PANDA'
he said: 
"that's $5" 
PANDA

a trick to escape any string: !:q

make bash do it for you!

$ # He said "that's $5" 
$ !:q
'/# He said "that'\'s $5"'

(3 strings squished together)

escaping and

here are a few ways to get a ‘ or “:

\' and \"
" ' " and ' " '
$'\''
"\""

person: '\'' doesn’t work!