Boolean Type

The Boolean type has two literal values: true and false. These values are not numeric values.

true is not equal to 1, and false is not equal to 0. true and false are case-sensitive.

The following code creates two boolean type variables:

 
<!DOCTYPE html>
<html>
<head>
    <title>Boolean Example</title>
    <script type="text/javascript">
          
        var isOK = true;
        document.writeln(isOK); //true
 
        var isNotOK = false;
        document.writeln(isNotOK); //true
              
    </script>

</head>
<body>
  
</body>
</html>
Click to view the demo
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Data Types:
  1. JavaScript Data Types
  2. typeof Operator
  3. The Undefined Type
  4. null Type
  5. null vs undefined
  6. Boolean Type
  7. Boolean() casting function
  8. The Literials of Number Type
  9. Octal Integer
  10. Hexadecimal
  11. Floating-Point Values
  12. Value range
  13. NaN
  14. Number Conversions:Number(), parseInt() and parseFloat()
  15. Number() function
  16. parseInt()
  17. parseFloat()
  18. The String Type
  19. String Literals and Escapes
  20. Get the String Length
  21. Converting to a String with toString() method
  22. Convert Number to String with radix
  23. Convert to String with String() casting function