There are actually 2 books called "The Art of War."

The one you are most likely to encounter at any given Booksazillion is by Sun Tzu. Written in China during the Spring and Autumn era, Sun Tzu explores the possibility of victory without violence and stresses the need to win before the battle has even begun via proper strategy and attitude.

A century or two later, during the much more violent Warring States era, a second "Art of War" was written by Sun Pin, perhaps a descendent of Sun Tzu. Editions of this book have appeared entitled both as "The Art of War" and "Military Methods." Its more about utter, crushing victory, and is not quite as generalizable (Sun Tzu's could apply to an argument as much as a war) and it was lost for centuries until researchers opened a Han dynasty tomb at Yin Chuan Shan and found it, along with several other works, including the oldest known copy of Sun Tsu's Art of War.

Cool books.