This book deals with measurement of stresses and strains in mechanical and structural components. This topic is related to such diverse disciplines as physical and mechanical sciences, engineering (mechanical, aeronautical, civil, automotive, nuclear, etc.), materials, electronics, medicine and biology, and uses experimental methodologies to test and evaluate the behaviour and performance of all kinds of materials, structures and mechanical systems. The different subjects exposed in this book are presented in a very simple and easy sequence, which makes it most adequate for engineering students, technicians and professionals, as well as for other users interested in mechanical measurements and related instrumentation.