Cocos2d-JS is a free open source 2D game framework. It can help you to develop cross-platform browser games and native applications. This framework allows you to write games in JavaScript. So, if you have already developed JavaScript applications, you don't have to learn a new language from scratch. Throughout this book, you will learn how to create almost any kind of cross-platform game using a familiar and intuitive language.
Before you start, let's see what software you need to install on your computer in order to start developing with Cocos2d-JS:
Firstly, you need a text editor. The official IDE for Cocos2d-JS coding is Cocos Code IDE, which you can download for free at http://www.cocos2d-x.org/products/codeide. It features auto completion, code hinting, and some more interesting characteristics to speed up your coding. If you are used to your favorite code editor, that's fine. There are plenty of them, but I personally use PSPad (you can find this at http://www.pspad.com/) on my Windows machine and TextWrangler (you can find this at http://www.barebones.com/products/textwrangler/) on the Mac. They are both free and easy to use, so you can download and have them installed in a matter of minutes.
To test your Cocos2d-JS projects, you will need to install a web server on your computer to override security limits when running your project locally. I am using WAMP (http://www.wampserver.com/) on my Windows machine, and MAMP (http://www.mamp.info/) on the Mac.
If you prefer, you can test your projects directly online by uploading them on an FTP space you own and call them directly from the web. In this case, you don't need to have a web server installed on your computer, but I highly recommend using WAMP or MAMP instead.
I personally use Google Chrome as the default browser to test my projects. As these projects are meant to be cross-platform games, it should run in the same way on every browser, so feel free to use the browser you prefer.
The latest information about Cocos2d-JS can be found on the official page http://www.cocos2d-x.org/wiki/Cocos2d-JS, while the latest version can be downloaded at http://www.cocos2d-x.org/download.
Note
Cocos2d-JS is updated quite frequently, but at the time of writing, the latest stable release is v3.1. Although new releases always bring some changes, all examples included in this book should work fine with any release marked as 3.x as there aren't huge changes in the roadmap.
You will notice the download file is a ZIP file that is greater than 250 MB. Don't worry. Most of the content of the package is made by docs, graphic assets, and examples, while the only required folder, at the moment, is the one called cocos2d-html5.