Earlier in this book, we talked about concurrency patterns and a bit about workers. We even brought the workers concept into play in the previous chapter, when we were building our logging systems.
Truly speaking, "worker" is a fairly generic and ambiguous concept, not just in Go, but in general programming and development. In some languages, it's an object/instantiated class, and in others it's a concurrent actor. In functional programming languages, worker is a graduated function return passed to another.
If we go back to the preface, we will see that we have literally used the Go gopher as an example of a worker. In short, a worker is something more complex than a single function call or programmatic action that will perform ...