Equity securities are financial instruments that represent an ownership interest in a company. The most common example is common stock. When an investor buys shares of a company's stock, they become a partial owner and may benefit from the company's growth and profitability.

Equity investors can earn returns in two main ways. First, the market value of their shares may increase, allowing them to realize a capital gain if they sell at a higher price. Second, some companies distribute part of their profits to shareholders through dividends. However, neither share-price appreciation nor dividends are guaranteed.

Common shareholders may also receive certain rights, such as voting on major corporate matters and electing members of the board of directors. The exact rights attached to shares can vary depending on the company and the class of stock. Preferred shares are another type of equity security. They typically offer different features, such as priority dividend payments, but may provide limited or no voting rights.

Unlike bondholders, equity holders do not lend money to a company. Instead, they own a portion of it and generally accept greater exposure to its business performance. If the company grows successfully, shareholders may benefit from rising share prices. Conversely, poor performance, economic conditions, competition, or changes in investor sentiment can cause the value of equity securities to decline.

In the event of liquidation, equity holders generally have a lower claim on company assets than creditors and bondholders. Common shareholders are usually paid last after the company's obligations have been met.

Overall, equity securities can offer significant long-term growth potential and possible dividend income, but they also involve market risk and the possibility of losing some or all of the invested capital.