A compass is an essential navigation tool that operates based on Earth's magnetic field. It consists of a small, freely pivoting magnetic needle, usually mounted on a low-friction bearing. The Earth itself acts as a giant magnet, with its magnetic field aligned along the planet's axis. The needle in the compass aligns itself with this magnetic field, with one end pointing towards the North Magnetic Pole and the other towards the South Magnetic Pole. This alignment occurs because the needle's magnetic properties cause it to respond to the Earth's magnetic field, creating a magnetic force that pulls it in the north-south direction. As a result, by observing the needle's orientation, one can determine the cardinal directions and navigate accurately over land or sea.