What you need for this book
In order to follow this book, you will need the Unity 3D software available at http://unity3d.com/unity/download.
You can use any version of Unity from Version 4.3, but I recommend the latest 4.x version, which at the time of writing was Version 4.5 (all screenshots have been updated to this version).
You must be familiar with Unity's basic workflow: the words GameObject, components, and Editor/Inspector should be familiar to you.
All the code pertaining to coding skills are available here and explained and commented where appropriate. So, if you are not familiar with them, you will still be able to understand them.
While working with this book, we will be using several freely available assets from the Web, plus a few I cobbled together myself (using my poor programmer art skills). All of these are available as a separate package download along with the book's code downloads mentioned further.