Star Trek Expanded Universe

The Star Trek expanded universe is an unofficial, fan-created term to describe an extrapolation of events which occur in the Star Trek Universe outside the scope of the television series and feature films. Information from the Star Trek "Expanded Universe" typically fills "holes" in the Star Trek story and timeline, with explanations of events which have never been adequately explained through live action productions. The term was first used in 1966 by writer D.C. Fontana to describe information put forth in the backstory of Doctor Leonard McCoy.