People use money to buy food, books, bicycles and hundreds of other things they need. When they work, they usually get paid in money. Most of the money used today is made of metal or paper. But in ancient times people used to use all kinds of things as money. One of the first kinds of money was shells(贝壳). In China, cloth and knives were used as money. Elephant tusks(象牙), monkey tails and salt were used in some parts of Africa. Rice was also a kind of money used by the ancient people on some islands. Cows and other animals were used as money, too. The first copper(铜) coins were made in China. They were round and had a square hole in the center. Different countries used different metals for their money. Later some countries began to make coins of gold and silver. But gold and silver were heavy to carry when people needed a lot of coins to buy something expensive. The Chinese were the first to use paper money. The first paper money looked more like a note than the paper money used today.