In this chapter, we will identify multiple concepts and principles that will prove essential for understanding solid-like behaviors of continuous materials. As noted in Chap. 1 , biosolid mechanics is an important field within biomedical engineering. For example, one quickly thinks of the importance of biosolid mechanics in understanding the mechanical function of the musculoskeletal and cardiovascular systems, particularly the primary functions of and injuries to bones, ligaments, and tendons as well as the pumping action of the heart. These are but a few of the obvious examples, noting that biosolid mechanics aids in understanding many other biological and clinical topics, ranging from the mechanical loads involved in the birthing process to the expansion of skin for creating skin grafts or designing artificial lens for cataract surgery. Indeed, biosolid mechanics is fundamental to the design of myriad medical devices and surgical instruments.