The Federal Insurance Contributions Act (FICA) is a U.S. law that mandates payroll taxes to fund two key social insurance programs: Social Security and Medicare. Employers and employees each contribute a percentage of wages, which helps provide benefits for retirees, disabled individuals, and certain survivors. FICA taxes are automatically deducted from employees' paychecks, ensuring a steady flow of funds to these programs. The current rates are set by law and can change over time, reflecting the need to support the growing number of beneficiaries as the population ages.