Question

If I want to something like:

foo="bar baz"
foo='bar baz'

Is it best practice to use double-quotes or single-quotes?

Answer 1

I tend to use double quotes unless I really need to use single quotes to stop variable interpolation or for other reasons.

Maybe this is part of my growing up with languages like Pascal, Fortran, and Basic which used double quotes and not single quotes. However, since most of the strings you use in BASH will do variable interpolation, you might as well get in the habit of using double quotes instead of thinking whether you need double quotes or single quotes in a statement. Also you’re variable might be:

foo='Thank you!'

now, but when you modify it:

foo='Thank you, $name!'

You don’t have to also remember to edit the quotes while, you’re at it.

In the few situations where you actually need single quotes, you can easily mentally shift the other way around.