The use of borrowed funds along with owned funds for investment is called leverage. The ratio of borrowed funds to own funds (or debt to equity) is called the leverage ratio. Leverage involves the use of various financial instruments, including options and futures.
Leverage also refers to the amount of debt used to finance a firm's assets. A firm with significantly more debt than equity is considered to be highly leveraged. Companies use debt to finance their operations. This increases their leverage because it enables them to invest in business operations without increasing equity.