Securities are instruments that hold some form of monetary value and can be traded. They represent financial assets that can be categorized into three main types: 1. Equity securities (stocks) denote ownership in a company, giving shareholders voting rights and dividends. 2. Debt securities (bonds) are borrowed funds that return interest at specified intervals and repay the principal at maturity. 3. Derivatives are contracts whose value depends on the price of an underlying asset, such as stocks, bonds, commodities, etc. Securities are critical for capital markets, facilitating the raising of capital for businesses and offering investment opportunities for investors.