Variables

Variables are used to store values (name = "John")

Before using a variable, you first need to declare it. You have to use the keyword var to declare a variable like this:

You can assign a value to the variable either while declaring the variable or after declaring the variable.

OR

Note:

Recently, JavaScript (since 2015) has started to allow the use of the const keyword to define a variable that cannot be reassigned, and the let keyword to define a variable with restricted scope.
Example: let name = "John"; or const temperature = 40;
Because it is a little complicated to describe the difference between these keywords, and because they are not supported in older browsers, we will most often use var.

Though you can name the variables as you like, it is a good programming practice to give descriptive and meaningful names to the variables.
Variable names should start with a letter and they are case sensitive. Hence the variables studentname and studentName are different because the letter n in a name is different (n and N).

Try this yourself:

You should see it like this:

And when you run it (save the program), you should get these results:

Challenge:

Lesson 1: Variables