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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops `do ... while` Loops

Chris Reich
Chris Reich
15,163 Points

What is the difference between using single and double quotes in js. Which should I use for writing concatenated strings

I was taught to write strings "like this" but I see the instructor in the videos writing things like( '<h1>You guessed the number!</h1>'); Is there a difference between the using the single and double quotes and what is it?

2 Answers

Nicholas Olsen
seal-mask
.a{fill-rule:evenodd;}techdegree
Nicholas Olsen
Front End Web Development Techdegree Student 19,341 Points

In Javascript there is no meaningful difference between the two. In practice, single quotes are just more convenient. Also, you need to escape whatever type of quotes you are using.

var stringOne = 'It\'s a girl!';
var stringTwo = "It's a girl!";

var stringThree = 'He said, "I don\'t want to."';
var stringFour = "He said,\"I don't want to.\"";

Things can also get hairy when using regular expressions.

My personal preference is to just stick to one, and use the other when you have to.

Nicolas Hampton
Nicolas Hampton
44,625 Points

Also, keep in mind that when you get to formatting JSON data, valid JSON only takes the double quotes. The choice to use either single or double in the rest of a Javascript project is personal, however, just try to keep it consistent to avoid hard to find errors.

Chris Reich
Chris Reich
15,163 Points

Thanks. The examples were helpful.

There is no preferred method, either single or double quotes are OK.. You can use either. However if you are using one form of quote in the string, its a good idea use the other as the literal.

alert('Say Hello');  // Say Hello
alert("Say Hello"); // Say Hello

alert('Say "Hello"'); // Say "Hello"
alert("Say 'Hello'"); // Say 'Hello'