Declare Variables in JavaScript
Before using a variable, you first need to declare it. You have to use the keyword var to declare a variable like this:
var name;
Assign a Value to the Variable
You can assign a value to the variable either while declaring the variable or after declaring the variable.
var name = “John”;
OR
var name;
name = “John”;
Naming Variables
Though you can name the variables as you like, it is a good programming practice to give descriptive and meaningful names to the variables. Moreover, variable names should start with a letter and they are case sensitive. Hence the variables student name and studentName are different because the letter n in a name is different (n and N). Try this yourself: