A derivative is a security which “derives” its value from another underlying financial instrument, index, or other investment. Derivatives are available based on the performance of stocks, interest rates, currency exchange rates, as well as commodities contracts and various indexes. Derivatives give the buyer greater leverage for a lower cost than purchasing the actual underlying instrument to achieve the same position. For this reason, when used properly, they can serve to “hedge” a portfolio of securities against losses. However, because derivatives have a date of expiration, the level of risk is greatly increased in relation to their term. One of the simplest forms of a derivative is a stock option. A stock option gives the holder the right to buy or sell the underlying stock at a fixed price for a specified period of time.
    衍生工具是一種金融工具，它是從其他原生金融工具如指數(shù)衍生出來的。衍生工具的獲得建立在證券、利率、匯率、商品合同以及各種指數(shù)。衍生工具給購買者一個杠桿效用促成以更低的成本購買實(shí)際需要的基礎(chǔ)工具。那么如果正確使用衍生工具的話，就可以在投資組合中套期保值?？墒茄苌ぞ哂幸粋€截至日期，所以風(fēng)險程度很大程度上取決于它的期限。最簡單的衍生工具形式是股票期權(quán)。股票期權(quán)使得持有者有權(quán)在特定時期里以一個固定價格買賣底層股票。