"Double quotes" or 'single quotes'??

Double unless i want to paste doubles

Depends, I know that in theory in PHP single quotes are slightly more performant because they don't do variable interpolation, which might be relevant I guess?

On the whole I prefer singles, but I know that's generally an aesthetic thing for me.

In C# we use (') for char and (") for string.

If you have the luxury of choice, use single, why bother holding shift key??

@KnightsOfCode
JavaScript and php also give you freedom of choice

@KnightsOfCode Perl also gives you the same choice as PHP I believe; double does variable interpolation where single doesn't. Not 100% on that though, they might be the same in Perl.

Ruby: Double quotes for interpolation. Single quotes everywhere else.

Single quotes always.

Double quotes only for html-attributes.