The Discworld is way too complicated to explain, unless perhaps if you have a degree in astrophysics or something....so I'll just sum up the story here. This one introduces us to Rincewind, a cowardly and inept wizard that never finished wizard school and only knows one spell (but he can't even remember that.) Actually, a summery is right here.
This book was a lot of fun. Once you get the basic idea of Discworld, which you can basically just expect the most absurd everything, you can enjoy Rincewind on his many mis-adventures with the foreigner Twoflower and The Luggage.
There's nearly 30 of these damn books and I'll get around to reading them all someday. The good thing is that they are really set up in different storylines with different characters...there's the Rincewind ones, Watchmen ones, Witches, and the ones about Death. I'm going to read the second Rincewind book and then probably jump to the first books in the Watchmen and Death series. Anyways, as much as I liked this book, it is said that the books get a lot better as they go on as Pratchett really finds his groove in his monstrous creation that is Discworld.