This introduction to differential geometry is now available in paperback. Stoker makes this fertile branch of mathematics accessible to the nonspecialist by the use of three different notations: vector algebra and calculus, tensor calculus and the notation devised by Cartan, which employs invariant differential forms as elements in an algebra due to Grassman, combined with an operation called exterior differentiation. Readers are assumed to have a passing acquaintance with linear algebra and the basic elements of analysis.