I remember seeing the first edition of this book at a book fair, and when I joined medical school, this was my trusted companion.
It provides the facts in a comprehensive but understandable manner and the information is organised extremely logically and is very easy to follow. It has long since been on my bookshelf and I only recently bought the 4th edition as my 2nd edition was looking worse for wear, having been read and re-read so often. If you like to keep asking 'why' in medicine, then this is the book for you!