Three subjects of major interest are contained in this textbook: Linear elasticity, mechanics of structures in linear isotropic elasticity, and nonlinear mechanics including computational algorithms. Engineering and mathematics are in a reasonable balance: After the simplest possible, intuitive approach follows the mathematical formulation and analysis. Computational methods occupy a good portion of the book. There are several worked out problems in each chapter and additional exercises at the end of the book. Very often, mathematical expressions are given in more than one notation. The book is intended primarily for students and practising engineers in mechanical and civil engineering. Most of them will be faced with problems of advanced materials and should have a correct understanding of the basic ideas even if they use software to solve them. Students or experts from applied mathematics, materials science and other related fields will also find it useful.