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6. Close the Settings window. JavaScript is now enabled in Microsoft Edge.
How JavaScript Works on a Webpage?
JavaScript is a text-based programming language that can be used on both the client and server sides to make web
pages interactive.
The steps below demonstrate how JavaScript interacts with the web page:
1. A request is sent to the server when the user types an address or URL into the browser.
2. The server accepts the browser’s request and sends the page back to it.
3. The page is rendered for HTML tags and the contents are displayed by the browser.
4. If a page contains JavaScript code that is enclosed by tags, the code is handled by the JavaScript interpreter.
5. This code can handle user-initiated events such as clicking a button, rolling the mouse, or submitting a form,
among others.
6. It makes the web page interactive by detecting and responding to what is happening on the page.
7. It has the ability to modify the appearance of a web page or its contents dynamically.
8, It has the ability to read and authenticate cookies.
How JavaScript Works on a WebPage
Web Browser
HTML Parser
Load
Parse HTML
WebPage
DOM
Update
Load
CSS Parser
CSS Parser
Run Code to modify
Load
JavaScript Engine
4.7 BASIC STRUCTURE OF A JAVASCRIPT PROGRAM
JavaScript cannot run on its own because it is a scripting language, and hence, needs to be embedded within an HTML
code. The basic structure of a JavaScript program is as follows:
<HTML>
<HEAD><TITLE></TITLE></HEAD>
<BODY >
<SCRIPT TYPE="text/javascript">
...
Write JavaScript code here
...
...
286 Touchpad Web Applications-XI

