<span class="SFPTagline"> From SCIFIPEDIA </span>

Genres are styles of creative works. For example, a monster movie will tend to have a number of elements in common: not just the fact that there is a monster, but the emotional feel of the films will be similar. The cinematography and music may also be recognizably those of a "monster movie".

Themes, on the other hand, indicate a similarity of content. Time travel can be treated in many different ways. While you can watch a movie for a minute and know that it is in the sword and sorcery genre, the same is not true of time travel films.

Genre in the singular is a general term for works of science fiction/fantasy/horror.