Klin Zha is similar to Chess in that it is an abstract board game between two players. Moving pieces take opposing pieces in the same way as chess. The most notible difference, though, is that it is played on a triangular board with triangular spaces. Also, unlike chess, the initial setup of the pieces is not standardized, players may arrange their pieces in any manner they choose within their "point" of the board.
On the website, one can find the full rules for this games, several variants, remarks on Klingon culture and how this games fits into it, photo's of sets, sample games, strategic hints, etc.
Larry Smith wrote the following about this book in an email of February 19, 1999:
The story deals with the story of Captain Krenn and the game is a recurring theme in his life. The scene on the cover of the book, however, is not a game of klin-zha in progress but one of standard chess - which Krenn thinks of as "the earther klin-zha" - which Krenn played for the first time when he met a very young Mr. Spock while he was visiting Earth in a diplomatic capacity. The game described in the book was standard chess, not the 3-d chess varient made famous in the TV series.Klin-zha is interesting because UNlike chess, the many many varients are accorded the full respect of the grandmasters of the game. Each varient reflects some different interpretation of the game's relevance to the "real" world. It would be as if Karpov was expected to be a master of a half-a-dozen varients of chess instead of one standard game.