A compass is a navigational tool used to determine direction relative to the Earth's magnetic field. It typically consists of a magnetized needle that aligns with the Earth's magnetic north and south poles, allowing users to find their bearings. The needle points towards the Earth's magnetic north, which is close to but not exactly the same as true north. By using a compass, individuals can orient themselves and navigate accurately, making it an essential tool for outdoor activities, exploration, and map reading.