JavaScript Variable Types

JavaScript supports five different types of variable. These variable types are outlined in the following table together with a brief description of each type:

Type	Example	Description
boolean	true, false	The boolean variable is used to record a value of either true or false. Internally this is essentially stored as 1 for true and 0 for false.
number	1, -31, 0.023	The number variable holds any type of number, either an integer or a real number.
string	"Hello World!"	The string variable type stores a string of characters, typically making up either a word or sentence. string variables can also be assigned empty strings.
function	any user defined function	A function is one of the basic building blocks of most programming languages including JavaScript. Functions are used to break up a script into clean, reusable modules. Functions are covered in a later chapter.