What is the main reason that drama is different from other forms of literature?

drama is collaborative in nature where it requires actors, stage, audience, play write etc. more over drama is written in dialogue with act and scene. whereas other literature genre like poem and novel. poem is popularly written in stanza with rhyme scheme. but novels they are written in chapter.

you may find little similarities between them i,e it is based on fiction or nonfiction. you should also keep in mind that they are not same.