The Null Type : Introduction « Number Data Type « JavaScript Tutorial






  1. JavaScript Tutorial
  2. Number Data Type
  3. Introduction

The Null type, has only the special value null.

NUll is also its literal.

The value undefined is actually a derivative of the value null, so JavaScript defines them as equal to each other.

alert(null == undefined);    //outputs "true"

Undefined is the value assigned when a variable is declared and not initialized.

Null is the value used to represent an object that doesn't exist.









5.1.Introduction
5.1.1.Numbers
5.1.2.Number() Object
5.1.3.Variables are loosely typed.
5.1.4.Built-in Values
5.1.5.Special Numerical Values
5.1.6.Primitive and Reference Values
5.1.7.Primitive Types
5.1.8.The Undefined Type
5.1.9.The Null Type
5.1.10.The Boolean Type
5.1.11.The Number Type
5.1.12.Number.MAX_VALUE and Number.MIN_VALUE define the outer bounds of the Number value set
5.1.13.NaN stands for Not a Number
5.1.14.JavaScript primitive values, Booleans, numbers, and strings, are pseudo-objects
5.1.15.Reference Types