Theoretical concepts are abstract ideas or principles that help explain phenomena in various fields, such as science, philosophy, and mathematics. They serve as frameworks for understanding complex systems and can guide research and experimentation. For example, the theory of relativity in physics provides insights into the relationship between space and time. These concepts often arise from observations and are tested through hypotheses and experiments. They can evolve over time as new evidence emerges, leading to refined or entirely new theories. In psychology, for instance, cognitive theories help explain how people process information and make decisions.