What do mean by NULL in Javascript?

[vidushi-tomar-7f335103 (Vidushi Tomar)]

What do mean by NULL in Javascript?

[sakshi-srivastava-f3c2a4a4 (Sakshi Srivastava)]

null denotes that currently that variable doesn’t hold any value but it will have later on. A null means absence of a value.

For eg: 
var a = null;
console.log(a);  // null

Doesn’t throw any error in case of no value.