A compass is a navigational instrument for determining direction relative to the earth's magnetic poles. The face of a compass usually highlights the four cardinal directions: North, East, South, and West. A magnetic compass works because the Earth is like a giant magnet, surrounded by a huge magnetic field. The Earth has two magnetic poles which lie near the North and South poles. The magnetic field of the Earth causes the magnetized needle of a compass to swing into a north-south position.

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