The Trill are actually two species, both sentient, which share a symbiotic relationship. In a joined Trill, the memories and character of the long-lived symbiont are merged with the body, memories, and skills of the host, and in some cases the personality. Although the majority of Trill are not joined, owing to a disparity in the populations of the two species, the joining is the aspiration of many young Trill. It was not a widely known fact that the Trill were in-deed two species joined in synthesis, but they are not considered secretive or deceitful - the matter of host and symbiont was simply a private matter.
Trill hosts and common folk alike frequently use the Hoobishan Baths as a means of entertainment, leisure or simple relaxation. It is a cultural focal point even, and people from across their world and beyond come regularly to visit it.
Trill scientists have lifetimes of experience, and are frequently scattered throughout the galaxy in search of new experiences. The Trill Research Committee brings together the research of these widespread Trill researchers.