The first of the book's three parts familiarizes the reader with the basics by discussing crucial experiments, a brief historical survey, and by following Feynman's route to the Schrdinger equation. The necessary mathematics is introduced along the way, to the point that all relevant theoretical concepts can be adequately grasped. Part II gets down to the nitty-gritty. As the theory takes shape, it is applied to various experimental arrangements. Many of these are central to the discussion in the final part, which aims at making epistemological and ontological sense of the theory. Pivotal to this task is an understanding of the special status that quantum mechanics attributes to measurements without dragging in "the consciousness of the observer." Key to this understanding is a rigorous definition of "macroscopic" which, while rarely even attempted, is conveniently provided in this book.