Shares (also called stocks or equity) are units of ownership in a company or fund. When you buy shares of a company, you become a partial owner, or shareholder, of that business. Each share represents a fractional claim on the company's assets and earnings. The value of shares fluctuates based on the company's performance, investor sentiment, market conditions, and broader economic factors. Shareholders may benefit from their investment in two ways: capital appreciation (the share price increases over time) and dividends (some companies distribute a portion of profits to shareholders).

For publicly traded companies, shares are bought and sold on stock exchanges like the New York Stock Exchange or NASDAQ. The number of shares you own relative to the total shares outstanding determines your ownership percentage—though for large companies, individual investors typically own a minuscule fraction of the business. Shares can also represent ownership in mutual funds or exchange-traded funds (ETFs), where one share of the fund represents proportional ownership of all the underlying investments the fund holds. Different types of shares carry different rights: common shares typically include voting rights in company decisions and variable dividends, while preferred shares usually have fixed dividends and priority in bankruptcy but no voting rights.