Money is anything people agree to accept in exchange for goods and services. Instead of trading five chickens for a new coat, you use money: bills, coins, or even digital numbers in a bank account. Money makes trade simple because everyone trusts it has value.

Throughout history, people have used seashells, salt, gold coins, and paper bills as money. Today, most money exists as numbers stored electronically in computers. When your parents pay for groceries with a credit card, they're transferring electronic money from their account to the store's account.

Money serves three main purposes. First, it's a medium of exchange, meaning you can trade it for what you need. Second, it's a unit of account, a way to measure and compare value: a bicycle might cost $200 while a book costs $15. Third, it's a store of value, meaning you can save it to use later instead of spending it immediately.

The phrase put your money where your mouth is means to back up your words with action, like doing something you claim to believe in. Money can't buy everything that matters: friendship, creativity, curiosity, or the satisfaction of mastering something difficult. But it does make the practical parts of life work smoothly, letting people trade their skills and time for what they need.