About the Tutorial JavaScript is a lightweight, interpreted programming language. It is designed for creating network-centric applications. It is complimentary to and integrated with Java. JavaScript is very easy to implement because it is integrated with HTML. It is open and cross-platform. Audience This tutorial has been prepared for JavaScript beginners to help them understand the basic functionality of JavaScript to build dynamic web pages and web applications. Prerequisites For this tutorial, it is assumed that the reader have a prior knowledge of HTML coding. It would help if the reader had some prior exposure to object-oriented programming concepts and a general idea on creating online applications. Copyright and Disclaimer Copyright 2015 by Tutorials Point (I) Pvt. Ltd. All the content and graphics published in this e-book are the property of Tutorials Point (I) Pvt. Ltd. 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Audience ........................................................................................................................................................... i Prerequisites ..................................................................................................................................................... i Copyright and Disclaimer ................................................................................................................................. i Table of Contents ............................................................................................................................................ ii PART 1: JAVASCRIPT BASICS ........................................................................................................ 1 1. JAVASCRIPT – Overview ............................................................................................................................ 2 What is JavaScript? .......................................................................................................................................... 2 Client-Side JavaScript....................................................................................................................................... 2 Advantages of JavaScript ................................................................................................................................. 3 Limitations of JavaScript .................................................................................................................................. 3 JavaScript Development Tools......................................................................................................................... 3 Where is JavaScript Today? ............................................................................................................................. 4 2. JAVASCRIPT – Syntax ................................................................................................................................ 5 Your First JavaScript Code ............................................................................................................................... 5 Whitespace and Line Breaks ............................................................................................................................ 6 Semicolons are Optional.................................................................................................................................. 6 Case Sensitivity ................................................................................................................................................ 7 Comments in JavaScript .................................................................................................................................. 7 3. JAVASCRIPT – Enabling ............................................................................................................................. 9 JavaScript in Internet Explorer ........................................................................................................................ 9 JavaScript in Firefox ......................................................................................................................................... 9 JavaScript in Chrome ..................................................................................................................................... 10 JavaScript in Opera ........................................................................................................................................ 10 Warning for Non-JavaScript Browsers ........................................................................................................... 10 4. JAVASCRIPT – Placement ........................................................................................................................ 12 JavaScript in <head>...</head> Section ......................................................................................................... 12 JavaScript in <body>...</body> Section ......................................................................................................... 13 JavaScript in <body> and <head> Sections .................................................................................................... 13 JavaScript in External File .............................................................................................................................. 14 5. JAVASCRIPT – Variables .......................................................................................................................... 16 JavaScript Datatypes...................................................................................................................................... 16 JavaScript Variables ....................................................................................................................................... 16 JavaScript Variable Scope .............................................................................................................................. 17 JavaScript Variable Names ............................................................................................................................ 18 JavaScript Reserved Words ........................................................................................................................... 19 6. JAVASCRIPT – Operators ......................................................................................................................... 20 What is an Operator? .................................................................................................................................... 20 Arithmetic Operators..................................................................................................................................... 20 Comparison Operators .................................................................................................................................. 23 Logical Operators ........................................................................................................................................... 26 ii Bitwise Operators .......................................................................................................................................... 28 Assignment Operators ................................................................................................................................... 31 Miscellaneous Operators ............................................................................................................................... 34 7. JAVASCRIPT – If-Else ............................................................................................................................... 38 Flow Chart of if-else ....................................................................................................................................... 38 if Statement ................................................................................................................................................... 39 if...else Statement ......................................................................................................................................... 40 if...else if... Statement ................................................................................................................................... 41 8. JAVASCRIPT – Switch-Case ...................................................................................................................... 43 Flow Chart ..................................................................................................................................................... 43 9. JAVASCRIPT – While Loop ......................................................................................................................