Understanding JavaScript Truthy and Falsy

Question

Can someone please explain JavaScript Truthy and Falsy, using the below sample data. I have read other threads but still confused.

var a = 0;

var a = 10 ==          


        

Answer 1

There's a simple way to check, which you can use now and forever:

function truthyOrFalsy(a) {
    return a ? "truthy" : "falsy";
}

To wit:

> truthyOrFalsy(0)
"falsy"
> truthyOrFalsy(10 == 5)
"falsy"
> truthyOrFalsy(1)
"truthy"
> truthyOrFalsy(-1)
"truthy"

Also see a list of all falsey values in JavaScript.