There are two basic kinds of beer: ales and lagers. It’s all about yeast’s preferences. Some yeasts like it on top, some prefer to be on bottom. Up until now, yeasts have not been more creative in their brewing positions, but we can always fantasize.
Ale yeasts like it on top and will ferment at higher temperatures (60-70°F) and so are quicker finishers than lagers (1-3 weeks). Usually ales are sweeter and have a fuller body, which really starts to take this sexual allusion to extremes.