html how to define a variable code example

Example 1: how to use variables in HTML

<!DOCTYPE html>
<html>
   <head>
      <title>HTML var Tag</title>
   </head>
   <body>
      <p>The equations: <var>2x</var> - <var>4z</var> = <var>2y</var> + 3 and
         <var>x</var> + <var>5z</var> = <var>3y</var> + 6</p>
   </body>
</html>

Example 2: html define javascript variable

<script>
var Number = 5;
var String = "Hi!";
var boolen1 = true;
var boolen2 = false;
var array = [11, "Hi!", true];
var object = {age:11, speach:"Hi!", likes_Bananas:true};
</script>