What a fun book! I am very fond of history books that are dedicated to explaining or displaying the everyday life of common citizens, not just the elite. Photographic postcards were very popular at the turn of the century, and people of all classes had pictures taken of themselves and sent them to their friends and relatives. Some are very funny, others display proud men at their work (often very dangerous jobs), others depict local artistic achievements and town or fair contest winners. Many of the postcards include the text of what was written on the back. If you'd like a glimpse of life during this time, I highly recommend this book.
A fascinating study of the popular picture postcards in the days when photography was new technology. The messages written on the cards are reproduced for some cards, and reveal something of the relationship between sender and recipient, e.g. "Waiting for your visit, hurry up" and "find me in this picture". The dogs all look curiously alike - no pedigreed house dogs here! The cards of the carnival sideshow attractions depict entertainment that would seem very odd today. Worth looking through several times, to see something new each time.
This is one of the classic books on postcards in general, and particularly on real-photo postcards. A nice range of images, very well reproduced, but perhaps the most used part is the glossary of backstamps and dating. There are newer books with more information (e.g., Real Photo Postcard Guide: The People's Photography), but this is still a useful one.