JavaScript Variable: Declare, Assign a Value with Example
Variables are used to store values (name = “John”) or expressions (sum = x + y).
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:
<html> <head> <title>Variables!!!</title> <script type="text/javascript"> var one = 22; var two = 3; var add = one + two; var minus = one - two; var multiply = one * two; var divide = one/two; document.write("First No: = " + one + "<br />Second No: = " + two + " <br />"); document.write(one + " + " + two + " = " + add + "<br/>"); document.write(one + " - " + two + " = " + minus + "<br/>"); document.write(one + " * " + two + " = " + multiply + "<br/>"); document.write(one + " / " + two + " = " + divide + "<br/>"); </script> </head> <body> </body> </html>