This textbook is designed for the undergraduate students (B.A./B.Sc.) of mathematics for a course in dynamics. It conforms to the course curriculum prescribed by UGC. The book will also be useful to the undergraduate engineering students for a course in engineering mechanics. The book presents the principle of kinematics describing the geometrical aspects of the motion of particles. It discusses the rectilinear motion with uniform and variable accelerations, the motion of a projectile in a vertical plane neglecting the air resistance, and the motion of a particle in resisting medium. The concepts of work, energy, power and impulse, impact of bodies, circular and cycloidal motions of a particle, motion of a particle under central forces, moments and products of inertia of different bodies, and motion of bodies with varying mass have been discussed in detail. In addition, the book describes the motion of a particle in three dimensions.