You should have a developer workstation that you can install Docker on and use to test out the examples included in this book. You will learn the most by actually trying each of the examples yourself instead of just reading over them. In addition, you should have access to at least one other, but preferably two or three other, servers to configure as a Docker swarm. These servers can be EC2 instances in AWS; or VMs on VMware Workstation or Fusion; or, worst case scenario, VMs in VirtualBox. All of the software used throughout this book is free or open source, so you should be able to try out everything you are learning here. Most of the examples will work equally well regardless of the OS you are using, and I have tried to call out the differences where appropriate. You should have an account created on https://hub.docker.com, and an account on https://github.com. All of the code samples have been tested by me, as well as by several reviewers, so if you don't get them to work, double-check the code and try again, or download the code from Packt and cut and paste it into your system, and then try again. You'll get the hang of it.