Cowboy Bebop is a space ship, on which the main characters of the series travel. Bounty hunting takes them to many corners of colonized space. You can see how and where people in year 2071 live. Its not an utopic beautiful future, its more of dark future full of gangsters, mafia and other criminals living on the edge of law. With enough money everybody can do just anything, which is not always legal.
Cowboy Bebop realy is kind of a western, full of bar fights or shooting. The cowboys just changed horses for space ships.
Great succes of the series in Japan and also in US brought a spin-off movie Knockin' on Heavens Door. On the other hand Cowboy Bebop had problems because of too much of violence in the series. Fortunately, the violence makes it more dramatic, more for adults and much more realistic.