truthy and falsy

In JavaScript, apart from Boolean values like true and false, all other values also have some boolean value corresponds to it.

    false
    ""(empty string)
    0(zero)
    undefined
    null
    NaN(not a number)

are considered falsy values.

So all the other values except these are, truthy values.

Ex "false" (String false) under conditional statement returns true.

This is very important concept in JavaScript.