"To run" refers to the action of moving swiftly on foot, using a rapid succession of steps. It is a fundamental form of locomotion for humans and many animals, often used for exercise, competition, or transportation. Running can vary in speed and distance, from short sprints to long-distance marathons. In addition to physical movement, "to run" can also describe the operation of machines or systems. For example, a computer can run software applications, while a car runs on fuel. This broader meaning highlights the versatility of the term in different contexts, such as sports, technology, and transportation.