Not exactly. The dog is taught to associate the sound of the clicker with doing something right.
Clickers are rarely used, because you can do the same with treats.
actually, i use a clicker and treats. i use the clicker to mark the desired behavior, so when he hears the marker (click) he knows he done good and that a reward (usually food treat, sometimes a ball) is coming. i like using the clicker because timing is sometimes very important, so i can quickly mark the exact behavior that i want.
That makes sense. Not sure I'm organized enough to plan anything more than verbal or food rewards.