Interactive Learning of Javascript for Free

The importance of Javascript as client side programming language is well known. Since the beginning of the Internet, Javascript has been defined as a robust, easy and flexible
programming language.

The scripts based on Javascript codes have many practical applications, for example in improvement of content management systems functionalities on the client side or in development of standalone AJAX applications which allow the refreshing of web page content without the need of reloading it.

Due to the extensive usage of Javascript codes as composing part of various web applications, the basic notions regarding Javascript coding techniques should be known if you need to customize certain aspects of Javascript based components or standalone programs. In order to learn Javascript or to solve a specific coding related problem, there are many resources available over the Internet for free, like tutorials, books, code examples and complete applications with full source code.

Marijn Haverbeke had the idea to publish an interactive online book which covers many topics related to Javascript programming language. The book is entitled " Eloquent JavaScript " and has the interactive character due to the presence of a console that allows users to test and modify the code examples from the book or to create new ones. The alert()Javascript function can be substituted (only on the console) with a new defined function print(), which does not create pop-up windows. In this way, the output of any script can be seen directly on the console.

The content of the book provides intuitive Javascript examples that come to demonstrate various definitions of concepts regarding variables flow control, data structures (objects and arrays), errors handling, OOP (object oriented programming) and more. As a useful remark for Javascript beginners, the semicolon (;) punctuation mark is not needed at the end of the lines in a Javascript code. In this book it is used (this is not a mistake), but it is not really necessary, because JavaScript will automatically perform the semicolon insertion.

In ensemble, the content of the book is well structured in presentation strategy, from the basics to advanced concepts. The Javascript scripts examples are objective relative to the discussed topics. The user interaction with the console will determine the perception and understanding of presented information to be performed in a more intuitive manner. If you want to read this book from your own computer, you can use a free offline web browser, like HTTrack to download it.