Classical Mechanics (Physics 281) is part of the core graduate student curriculum. The first part of this course focuses on Lagrangian formulation and Hamiltonian formulation of mechanics. Students should learn to set up the Lagrangian and/or Hamiltonian for systems under study, analyze the relevant symmetries, obtain the equations of motion, and solve them in certain cases. Students should learn to master the concept of and appreciate the importance of canonical transformations, Poisson brackets, and invariants. This course will also present the symplectic approach to the canonical transformation by introducing the concept of the Lie transformation and Lie Algebra. To assist the learning of other modern physics topics, such as special and general theory of relativity and quantum field theory, this course will introduce and use the languages of tensor and differential geometry when appropriate. The remaining part of the course deals with the traditional topics of classical mechanics such as rigid-body motion, central force problems, and small oscillations. This course will also give a brief introduction to nonlinear dynamics if time permits.