The discworld series is a fantasy series based on the discworld. This is a flat world on a disc, which moves through space on the back of four elephants who stand on the shell of the great space turtle A'Tun. There are various countries and major cities on the discworld, with many different types of people. Humans, Dwarfs, Trolls, Gnomes, etc. The books have different focuses. Many are focused on probably the biggest city, Ankh-Morpork. These books might focus on the night watch, lead by Commander Vimes, others on the Wizards who have Unseen University in the city. The wizards are generally stupid. Other books focus on the character death. Others focus on the witches who live up in the mountains. They are comedy fantasy books.
Hope that makes some sense.