Sometimes, basic questions must be raised, and this is what this book does: What do we understand by a "medium"? How do we observe "communication"? What does it mean to say that communication is mediated? How should we interpret the idea of immediacy? The background for raising these questions is this important book which was published by Jay Bolter and Richard Grusin in 1999. Although it was published only a few years ago, revisions -- or, at least, reconsiderations -- already seem to be needed. The chapters represent a wide spectrum of different cases and media -- from television to computer, film and mobile phone. The main effort of the book is to put concepts like hypermediacy, immediacy, remediation, communication and the desire for the real into debate and practice. In nine articles, the last one written by Bolter himself, the writers are discussing and reconsidering these fundamental concepts.