A compass, zhǐ nán zhēn, indicates north and south. It was invented by Chinese 2,000 years ago.
The ancient zhǐ nán zhēn looked like a spoon. When the spoon was put on a plate its handle could point to the south using magnetic fields.
Then Chinese used a little steel needle to replace the spoon. This made the zhǐ nán zhēn easier to carry.
600 years ago Zheng He, a famous eunuch of the Ming Dynasty, traveled to Southeast Asia and the Indian Ocean seven times. Zheng even reached the Red Sea with the help of the zhǐ nán zhēn. The invention boosted the development of navigation.