Stocks are shares of ownership in a corporation. When you buy stocks of a publicly listed company, you become a stockholder or shareholder of a company. In other words, you become part-owner of that company.
As such, you participate in that company's growth and future profits. Conversely, you may also lose if the company suffers a loss or performs below market expectations.
Note: It is also known as a Share, Equity or Security.
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