This book presents an introduction to the classical theories of continuum mechanics; in particular, to the theories of ideal, compressible, and viscous fluids, and to the linear and nonlinear theories of elasticity. These theories are important, not only because they are applicable to a majority of the problems in continuum mechanics arising in practice, but because they form a solid base upon which one can readily construct more complex theories of material behavior. Further, although attention is limited to the classical theories, the treatment is modern with a major emphasis on foundations and structurePreface. Acknowledgments. Tensor Algebra. Tensor Analysis. Kinematics. Mass. Momentum. Force. Constitutive Assumptions. Inviscid Fluids. Change in Observer. Invariance of Material Response. Newtonian Fluids. The Navier-Stokes Equations. Finite Elasticity. Linear Elasticity. Appendix. References. Hints for Selected Exercises. Index.