Javascript introduction

Javascript is an object based scripting language. Javascript is lightweight and cross platform.It is a programming language for HTML and web.

JavaScript is used to create interactive websites. It is mainly used for:

• Client-side validation
• Dynamic drop-down menus
• Displaying data and time
• Displaying popup windows and dialog boxes etc

Basically JS can change the HTML content and below is one example.

document.getElementById("example").innerHTML = "Hello JavaScript";

This example uses the method to "find" an HTML element (with id="example"), and changes the element content (innerHTML) to "Hello JavaScript"

Javascript Example:

<h2>Welcome to JavaScript</h2>  
<script>  
document.write("Hello JavaScript - First example");  
</script> 

Output:

Hello JavaScript - First example