This text, intended for advanced undergraduates, begins with an introduction to the mechanical properties of materials, general fracture mechanics, and fractures in brittle solids. This is followed by a detailed discussion of stresses and the nature of elastic and elastic-plastic contact. The discussion then turns to a description of stress fields and their role in the formation of cracks in brittle materials and of sub-surface damage in ductile materials. The book concludes with an overview of practical methods if indentation testing.