Can the reactive power be used?

The notion of reactive power was introduced a long time ago because of its advantages to describe the behaviour of a power system. Among these advantages are the facts that reactive power is a scalar quantity (therefore easy to manipulate) and that it is conserved over any network. Over time, the meaning of the original concept of reactive power has been lost and today the "reactive power" is used for the maximum reactive power that flows through a piece of electric network. The change of meaning is the origin of a few misconceptions that are present in almost every textbook today. This article reanalyzes the reactive power concept, identifies the present contradictions and defines clearly the differences between reactive and active power.