The term "legwork" refers to the investigative work that is done on foot, or through physical activity such as walking, surveillance, interviews and other activities that require being present in a specific location. It involves gathering information by visiting places, talking to people, observing events or conducting research in person rather than relying solely on technology or remote sources. In essence, it is the process of doing groundwork or field work to uncover facts and details about something through direct observation and investigation.