Single unless you need to use single quotes within quotes. Example let string = "I didn't like it"; You should use .eslintrc with Eslint plugin to help guide you.

It all depends on what situation you find your self

Single quotes seem to be more commonly used. Most javascript code standards follow this convention:

• StandardJS: Single quotes for strings – except to avoid escaping.
• Google JavaScript Style Guide: Ordinary string literals are delimited with single quotes ('), rather than double quotes (").
• Airbnb JavaScript Style Guide: Use single quotes '' for strings.

I PREFER double-quotes because I'm old school. Double quotes for strings, single quotes for chars. But, doing it the most accepted way is really the right way. Guess I gotta go change my code now... walks away, head hung in shame

Single quotes NOW that I came across this poll XD. (I'm justing starting out)

Doesn't really matter, use whatever you prefer, but stick to your decision!

Before I got into NodeJS, I used PHP extensively. In PHP, there is a difference between single and double quotes. I preferred single-quotes then and carried the habit on to JS.

Later, I found out about the Google JS Style Guide, which tells you to prefer single quotes. Since I mostly agree with that style guide, I always use single quotes (or template strings).