Of course, that sounds like a ridiculously unrealistic premise for a universe, but I learned through this book that that is exactly the point of everything in this world. In one word, the Discworld is just ridiculous. It takes everything epic fantasy worlds have, and then makes everything into a joke, too. So if you're looking for a story you're not really intended to suspend disbelief for, then this one works. It's a fantasy series, but its also a comedy.
The Colour of Magic itself is structured in a really strange way. It's a very short book, with a word count of sixty-five thousand words (which is pretty short for the things I've read lately). But there aren't really any chapters. It would be more accurate to say that there are about four chapters, but since they're so long I would call them 'parts'. The chapters are all individual stories, so it reads like a set of novelettes starring the same characters as they have a bunch of adventures.
But the story never takes itself seriously. There is a chest of Luggage made of special wood and it walks the line between character and tool, because I would say it has more personality than a lot of the people walking around. One of the main protagonists has a camera, but since this world doesn't have electricity (harnessing storm giant power is actually a running gag in the book) it functions because of a little tiny demon painting all of the pictures. Later in the book, there is an upside down mountain. The peak is at the base, in it just thickens as it scales skyward.
But one of my favorite things about the book is that the narration takes a sort of omnipotent perspective sometimes. It likes to poke fun at the protagonists, mentioning repeatedly that Fate is literally against him, and the perils he gets into are commonplace to him because he's so used to being in grave danger. That isn't to say he likes being in deadly situations, though. I think the fact that Rincewind is so "normal" in regards to our universe that it makes him relatable, especially when he gets thrown into ludicrous situations.
So, while the Discworld probably isn't my cup of tea, I can definitely understand why Pratchett is so successful. His writing is captivating, and quite humorous. He has about thirty books, branching into different series, and it gets so confusing that you have to look up a reading guide if you're interested. Don't let that deter you if any of this sounds interesting, though.