Most industrial robotic devices have an important characteristic in common, the axes of their SKCh joins are either parallel or orthogonal to each other. In this book, such architectures are referred to as Orthogonal Architectures, and an exhaustive analysis of their kinematics is introduced. Closed-form solutions are derived from this analysis for fast and efficient computations aiming at the simulation and control of robots. Chapters 4 to 11 are dedicated to introducing the algorithms for the inverse-kinematic-problem solution of the eight arrangements referred to the first three joints of a SKCh.