From the reviews: "The author points out that many important applications of semiring theory can be reduced to the problem of finding solutions of affine equations ... . theory with complete proofs as well as illustrating examples can be found. A carefully written index of applications and an index of terminology help the reader to find the numerous concepts mentioned throughout the book. Also an extensive bibliography (490 titles) is included to show the wide range of applications of the developed concepts in many areas ... ." (Udo Hebisch, Zentralblatt MATH, Vol. 1042, 2004)