===== Javascript Cheat Sheet =====

This is a summarized form of the [[http://www.w3schools.com/js/default.asp | JavaScript Tutorial]].

For reference JavaScript specifications can be found [[http://developer.mozilla.org/en/JavaScript_Language_Resources | here]] .

==== What is Javascript ====

  * JavaScript is the most popular scripting language on the internet and works in all major browsers.
  * It is a lightweight, interpreted language that is embedded into webpages to add interactivity.
  * JavaScript can read and write HTML page elements, react to events, validate data, create cookies.
  * JavaScript was invented by Brendan Eich of Netscape but is now known officially as ECMAScript (current version is ECMA-262).
  * A simple "Hello World" example <code html>
<script type="text/javascript">
<!--
document.write("Hello World!");
//-->
</script> </code>
  * JavaScript code may be located
    * In the head - executed when called
    * In the body - executed while loading
    * In an external file called from either the head or the body e.g. <script src="abc.js"></script>

==== Basic Syntax ====

  * JavaScript is case-sensitive.
  * Statements may omit the final semi-colon but should not.
  * Blocks may be grouped together using curly braces { }.
  * JavaScript uses java-style comments: // and /* */.
  * JavaScript variables are case-sensitive and must begin with a letter or underscore.
  * Variables are automatically declared when first used but should be explicitly declared using e.g. var a = 5;
  * JavaScript uses standard C/Java operators e.g. +-*/%, ++, +=, &&, ||, !, + (concatenation).
  * JavaScript uses C/Java comparators >,>=,==, !=, a?b:c. It also uses === to test equality of value and type.

==== Basic Structures ====

  *