A compass's singular purpose is to tell you what direction you are heading in at all times, which prevents you from getting lost. Typically, hikers and backpack travelers rely on compasses to get them to their destinations.

Features of a compass -- https://setcompass.com/CompassFeatures.htm

A compass rose, sometimes called a windrose, is a figure on a compass, map, nautical chart or monument. It is used to display the main directions (North, East, South and West). These are also called the cardinal directions.

The needle on a compass always points true north. In marine use, a compass can be used to adjust the path of a vessel so it stays on course. A compass can also help one detour from a charted course in order to avoid a storm or other hazard.