Derivative

A derivative is a financial contract whose value comes from something else, rather than having value on its own. That "something else" — called the underlying — can be a stock, a stock index, a commodity like oil or gold, a currency pair, an interest rate, or even a basket of other assets. The derivative itself is just an agreement between two parties about what happens based on how that underlying moves.

The mechanics vary by type, but the general idea is that the contract sets terms in advance: a price, a date, and what each side is entitled to or obligated to do. An option gives the buyer the right (but not the obligation) to buy or sell the underlying at a set price before a certain date. A future obligates both sides to transact at a set price on a set date. A warrant, issued by a company, works like an option but typically leads to new shares being created if exercised. In every case, you can hold the derivative and never touch the underlying asset itself.

The nuance that trips beginners up is that derivatives usually give you leveraged exposure — you control a large amount of underlying value while putting up a much smaller amount of money. This cuts both ways: gains and losses are both magnified relative to the cash you've committed, and it's possible to lose more than your original outlay on some derivative types, particularly futures and certain option positions (selling, or "writing," options carries different and often larger risk than buying them).

Another point of confusion is that "derivative" is a category, not a single product — options and futures behave very differently from each other even though both are derivatives. Each type has its own rules on expiration, margin (the collateral you must post), and what happens if you do nothing before the contract ends.