Abstract

We give a short, critical review of the issue of decoherence. We estab- lish the most general framework in which decoherence can be discussed, how it can be quantified and how it can be measured. We focus on environment induced decoher- ence and its degree of usefulness for the interpretation of quantum theory. We finally discuss the emergence of a classical world. An overall emphasis is given in pointing at common fallacies and misconceptions.