Some guidebooks tell you what to see, where to find it, when it's open and how much it will cost to get in. This book tells you why to go see it, how its history imbued it with character and gave it its shape, and what sets the destination apart.
Which is not to say that the book is without practicalities. The first page is a subway map is perfectly located, usefully clear, and is augmented on the following two pages with all of the tourist information and services contacts you'd likely need. Also, the walking tours are excellent, picking out a selection of sites in a given area and suggesting some routes rather than outlining step-by-step where you should go.
It's a small book that fits in your pocket and gives you very readable "colour" as you prepare your trip and travel the city.