There are many houses and other groups in the novels. The most well-known ones being House Atreides, House Harkonnen, the Bene Gesserit, and the Fremen. But Frank Herbert’s created many other groups in his fictional universe, some of which gradually evolved, and some which just died out.
Which is the one you are most fascinated with? And why do you find them so interesting?
The people living under the Atreides on Calidan are the only ones that have half decent lives while still living under an authoritarian dictatorship.
The spice smugglers are probably the most free people in the books.
Being a facedancer late in the books would be fascinating if one could be truely independent and free.