This book is split into chapters based on the traditional school subjects, such as geography, history, maths, and then within each chapter split into 'typical things we were taught', ranging from the list of British kings to trigonometry to Charles Dickens.
There are certain chapters you'll skip, either because they were your specialist subject at university or because you're still not interested years later. But there are chapters you'll definitely be saying "I used to know that!" for.
It doesn't take very long to read the entire book, but that's only half the usefulness, because my copy will be taking a prominent place on my shelf- because next time anything that relates to these subjects comes up, I'll remember (I hope) that if I've forgotten it, this is the first book to turn to.
My only criticism is that perhaps 192 pages is a little ungenerous and the authors could easily have found an extra 50% of stuff that we've also forgotten from school. Or maybe that's being saved for a sequel.