Compass needles are small, directional instruments that are essential for navigation. The term compass needles refers specifically to the small magnetic needles that are used to indicate the direction of the earth's magnetic field, which is used to determine the direction of true north. Synonyms for compass needles include magnetic needles, magnetic compass needles, directional needles, and compass pointers. These terms are all used to describe the same basic instrument, the small needle that points north in a magnetic compass. While there are many different types of compasses available today, compass needles remain an important and reliable tool for navigation in many different settings.