If you have never used Go before, have no fear. It has a gentle learning curve and is simple enough to learn in just a day or two. The best place to start is https://tour.golang.org/. This is a basic tour of the Go programming language. If you have already gone through the tour, then you should already have the foundation to make it through this book just fine. If you are working through this book and have not taken the tour, you may come across a concept you are not familiar with that is not explained here. The tour is a good place to learn and practice.
Since there are only 25 reserved keywords in the language specification, it is short enough to be understood by "mortals". You can read more about the specs at https://golang.org/ref/spec ...
