The Colour of Magic is the first book in the Discworld Series. The Discworld is a flat world supported on the back of a giant turtle (sex unknown). The Disc is made up of continents and countries some of which bear some vague resemblance to our own countries and cultures. Although a series almost all the books are books in their own right and can be read independently of each other.
The Colour of Magic introduces Rincewind, a one-spell wizard and freelance interpreter, who meets Twoflower, the Discworlds first tourist. The formers cowardice and the latters simplicity manage to burn down Ankh-Morpork, but that is only the beginning of their troubles. They journey to the Rim of the World, as dragons, gods and Death await them...
The Colour of Magic is a little slow to start but once you get into it is is pure genius. The book doesnt introduce you to the discworld so much as drop you in it from the start. Only a few places in the disc are mentioned in the book and more are revealed as you read more of the series.
Besides being the first Discworld novel it is also the first book in the Rincewind sub-cycle and it introduces both him and the Luggage. Rincewind is probably not my favourite Discworld character but this is definitely one of Rincewinds best books and worth reading.
The books are generally parodies of real life and these are usually easy to spot. There are smatterings of philosophical thought as well throughout this and the other books. For those of you who thought that Wizards were the realm of JK Rowling then you guys have yet to experience Pratchett.