Discworld novel 1

The main character is an incompetent and cynical wizard named Rincewind. He involuntarily becomes a guide to the rich but naive tourist from the Agatean Empire, Twoflower. Forced to flee the city of Ankh-Morpork to escape a terrible fire that was caused by a bartender who misunderstood the concept of insurance, which Twoflower told him about, they begin on a journey across the Disc.