Margin

Borrowed money from a broker used to purchase securities, effectively leveraging a trader's buying power. Under Regulation T, U.S. brokers can lend up to 50% of a stock purchase's value as initial margin. While margin amplifies gains, it equally magnifies losses and introduces the risk of a margin call if the account value drops below the maintenance requirement. Margin is also used differently in futures markets, where it refers to a good-faith performance deposit rather than a loan.