The history of physics ranges from antiquity to modern string theory. Since early times, human beings have sought to understand the workings of nature--why unsupported objects drop to the ground, why different materials have different properties, and so forth. The emergence of physics as a science, distinct from natural philosophy, began with the scientific revolution of the 16th and 17th centuries when the scientific method came into vogue. Speculation was no longer acceptable; research was required. The beginning of the 20th century marks the start of a more modern physics. Physicists began to study the atom, with its electrons and its nucleus. Then they began to look at the fundamental question of the forces that hold the nucleus together and the particles that account for the natural forces. This book approaches the history of physics from a biographical point of view, considering people to be more interesting than things, and the combination of the two more interesting than the sum of the individual parts. After a brief overview of classical and modern physics, 336 one-page biographies of individuals who have made significant contributions to the field of physics are presented.