In terms of Star Trek first time fics, the "pon farr" story wins hands down for quantity. Pon farr refers to the "mating ritual" of the cold inhabitants of Vulcan: once every seven years, the males go into heat and must engage in sexual activity with a mate, or else they will die. Typically in this kind of story, Kirk and Spock will be trapped somewhere together while Spock enters ponn far... and Kirk is forced (or eager) to accomodate his friend.

Another popular theme is billed under "Hurt/Comfort", a term which also applies to certain non-slash fics. This involves one character being hurt - physically or psychologically - and the other offering comfort and care. In slash fic, of course, this generally leads to the development of a deeper relationship. Leslie Fish's Shelter, published in 1976, is an example of both a First Time and a Hurt/Comfort story.

Many slash fics also take the form of humor or parody, and some of them are action/adventure related, where the relationship between the two main characters is assumed to already exist and is used as an accepted background to the stories. Still other authors have written stories about sex, and nothing more. There are also "alternate universe" stories, like Ray Newton's The Prize.

The main point of slash fiction - and that which authors insist distinguishes it from pornography - is the fact that the stories are meant to explore and illustrate a relationship which is deeply meaningful, a 'partnership' between two beings who know and love each other. There is meant to be much more to the stories than the concept of physical attraction, though sensuality certainly plays a role.