The author is a geography professor whose point in writing the book is that we see maps as capturing an objective reality — they're right there, before our eyes — but they're often shaped by the agendas, beliefs and assumptions of the cartographer. Late 1800s historical maps of the US, for instance, showed the 13 colonies against an empty wilderness — no sign native tribes were ever there. An old boundary map may have little in common with the modern reality as trees die, hills wear away and rivers change course. The way an environmental-hazards map visualizes nuclear danger from a power plant may distort our perception risk (or our safety). Landscape features that used to be "n-word" hill or lake have been renamed for obvious reasons. A good book about an interesting subject.