Structural biology deals with structural analysis of living material (formed, composed of, and/or maintained and refined by living cells) at every level of organization.

Early structural biologists throughout the 19th and early 20th centuries were primarily only able to study structures to the limit of the naked eye's visual acuity and through magnifying glasses and light microscopes. In the 20th century, a variety of experimental techniques were developed to examine the 3D structures of biological molecules. The most prominent