Naming Variables : Variables « Language Basics « JavaScript Tutorial

1. JavaScript Tutorial
2. Language Basics
3. Variables

The first character of the name must be a letter or an underscore (_).

All characters following the first character can be letters, underscore, or digits.

Letters can be either upper or lowercase.

JavaScript does distinguish between the two cases.

All the following variable names are legal:

var test;
var $test;
var $1;
var _$te$t2;