A stock is a type of investment that denotes ownership in a portion of the issuing company. Shares, also known as units of stock, entitle its owners to a share of the company's assets and income in proportion to the number of shares they possess.

There are two types of stocks, common stock and preferred stock. Common stockholders are given voting rights on company decisions, while preferred stockholders are given no voting rights.

The stock market is an area where regular buying and selling of public stocks take place. There are various stock exchanges such as the New York Stock Exchange and Chicago Board Options Exchange.