You should have a powerful PC running a Linux distribution, preferably Ubuntu 16.04 LTS.

You can use a laptop or desktop with a graphics card, and RAM of 4-8 GB is preferred. This is actually for running high-end simulations in Gazebo, as well as for processing point clouds and computer vision.

You should have the sensors, actuators, and I/O boards mentioned in the book and should be able to connect them all to your PC.

You also need Git installed to clone the package files.

If you are a Windows user, then it will be good to download VirtualBox and set up Ubuntu on it. You can have issues when you try to interface real hardware to ROS when working with VirtualBox. So, it is best if you can work from a real Linux system.