If you don't have the Unity 3D game engine application installed on your PC yet, do that now! The full-featured Personal Edition is free and runs on both Windows and Mac. To get Unity, go to https://store.unity.com/, select the version that you want, click on Download Installer, and continue following the instructions. This book assumes you have version 2017.2 or later of Unity.

For you beginners out there, we're going to take this first section nice and slow, with more hand-holding than what you'll get later on in the book. Furthermore, even if you already know Unity and have developed your own games, it may be worthwhile to revisit the fundamental concepts, since the rules are sometimes different when designing for virtual reality.