This book investigates the geometry of quaternion and octonion algebras.
Following a comprehensive historical introduction, the book illuminates
the special properties of 3- and 4-dimensional Euclidean spaces using
quaternions, leading to enumerations of the corresponding finite groups
of symmetries. The second half of the book discusses the less familiar
octonion algebra, concentrating on its remarkable "triality symmetry"
after an appropriate study of Moufang loops. The authors also describe
the arithmetics of the quaternions and octonions. The book concludes
with a new theory of octonion factorization. Topics covered include the
geometry of complex numbers, quaternions and 3-dimensional groups,
quaternions and 4-dimensional groups, Hurwitz integral quaternions,
composition algebras, Moufang loops, octonions and 8-dimensional
geometry, integral octonions, and the octonion projective plane.