This document discusses using HTML5 and JavaScript to develop games that can run on multiple platforms. It outlines several game engines and frameworks like Phaser.js, Melon.js and Crafty.js that use HTML5 technologies to build 2D and 3D games. It also mentions tools for developing games targeting mobile, desktop, consoles and other platforms. The document provides code examples for basic canvas animation and advises starting simple, choosing the right platform and having fun learning.