I was lucky enough to receive a signed copy. This is a hardcover coffee table book for steampunk/victorian children or adults (but smaller). Every page is a full page poster of the letter represented. The artistry is basic enough for children to enjoy but detailed and clever enough to excite adults and make them wisely think to pack it away as a treasure and not put it into the resale pile. D is for difference engine, everyone!!! (But G is for goggles.)