What does “use strict” do in JavaScript, and what is the reasoning behind it?

Question

Recently, I ran some of my JavaScript code through Crockford\'s JSLint, and it gave the following error:

Problem at line 1 character 1: Missing \"use

Answer 1

use strict is a way to make your code safer, because you can't use dangerous features that can work not as you expect. And, as was written before, it makes code more strict.