A barter system is an ancient method of exchange where goods and services are traded directly for other goods and services without using money. For example, if a farmer has apples and needs bread, they can trade a certain amount of apples with a baker who has bread. This system relies on mutual agreement about the value of the items being exchanged. Barter systems can be beneficial in situations where currency is unstable or unavailable. They encourage direct trade and can help build community relationships. However, they also require a double coincidence of wants, meaning both parties must want what the other offers at the same time.