Based on the great Ask MetaFilter thread from 2007: What single book is the best introduction to your field (or specialization within your field) for laypeople?.
The whole thing’s worth a read but a while back I decided to go through, give it a squeeze, and extract the juicy bits: the books themselves. So below is a list of books, grouped into topics, as recommended by the thread.
And, of course, this is quite an arbitrary list of subjects and books — ask the same question of a different group of people and most of the list will no doubt be different (although the books that are the same… those will be the interesting ones).