Based on data gathered by the author as part of ACM's International Risks Forum, this book contains accounts of mishaps attributed to computers and the people using them--some humorous, and some tragic. Neumann characterizes different kinds of computer-related risks, discusses risk causes and effects, and considers their implications. He also suggests ways to minimize risks in the future.
It is fascinating how many ways things can go wrong.
I've read other books along similar lines and wish I could find the titles. I remember the theme of one of them was that multiple small problems left unfixed are a setup for disaster.