Physics is a laboratory-based science. Experiments reveal the observable properties of the natural world, and theories provide an understanding of the observations. Mathematics serves as the essential language for the analysis of experiment and theory.

The work physicists do can be classified as basic or applied. The scientist doing basic research typically works in a university or national laboratory, and is interested in learning about the fundamental processes of nature. The applied physicist wants to develop uses for knowledge through technological advances, and is employed most often in an industrial setting.

Physicists usually choose to be either experimentalists or theorists. The experimenter uses apparatuses designed to test hypotheses and theories, to make unexpected discoveries of new phenomena, or to develop new applications of ideas. The theorist uses that data to develop new explanations, hypotheses, or theories. Occasionally a particularly broad scientist can act as both experimentalist and theorist. Physicists may also use the computer to simulate a physical system and generate data from observations of the simulation in order to gain new insights into real systems.