Theatre has purpose, be it entertainment, exploring different opinions like in feminist, or trying to see new avenues of story telling. Because of these different ideals of what theatre and the cultures in different nations, theatre has branched out to these different art-forms, even time periods make for differences. no one theatre is better than the other as they all have a purpose but some performances can fail if they do not live up to some of the expectations of their theatre type.

Here are some theatrical types I have noticed to have a central theme.
Butoh- the horrors of the bombs and the twisted nature.
Feminist- why are there stereotypes of gender roles and why should we continue to abide by them.
Performance art- the visual body as an art rather than a story as art.
Musicals- art of combining dance, song, and character acting.
Opera and Operetta- the narration of stories through singing or a mix of singing and acting
Regional theatre- plays and performances of any type, expressing the problems of the country they are in
Postmodernism- the recreation or re-written of previous stories as theatre