Difference between == and === in JS [duplicate]

This question already has answers here: Closed 11 years ago.

Possibl开发者_如何学JAVAe Duplicates:

Difference between == and === in JavaScript

Javascript === vs == : Does it matter which “equal” operator I use?

What's the difference between == and ===? Also between !== and !==?

---

There are lots of answers to this question on Stackoverflow already.

Short:

== only compares values

=== compares values + type

---

var check1 = '10',
    check2 = 10;

check1 == check2 // true
check1 === check2 // false

---

"==" means equals, whereas "===" means identically equal.

In short, "==" will try and coerce/convert the types of values when doing a comparison, so "2"==2, whereas "===" will not.