Its file extension is .js and used in on page and off page as js file which is attached with the HTML document. It is very usable for client side scripting and perform any type of functions.
(iii) Developing Web and mobile app
(iv) Developing various platform's games
(v) Other Apllication development
(vi) Creating sever applications
(vii) It is also used in robotics applications.
(i) On page scripting: The script is writen in <script></script> html tags under head tag.
<meta name="" content=""/>
<h1> Heading 1</h1>
<p>My paragraph goes here.</p>
There are folloing role of java script in web development: