Financial institutions are entities that provide financial services to their clients or members. These include commercial banks, investment banks, insurance companies, pension funds, and credit unions. They accept deposits, make loans, underwrite securities, manage investments, and provide insurance. Their role is to channel funds from those who have surplus capital (savers) to those who need capital (borrowers or investors), thereby facilitating economic growth.

Financial markets are platforms where financial instruments such as stocks, bonds, currencies, and derivatives are traded. These markets can be broadly categorized into money markets (for short-term debt) and capital markets (for long-term debt and equity). Key examples include stock exchanges (like the NYSE or Nasdaq) and bond markets. These markets provide price discovery, liquidity, and a mechanism for risk transfer.

Financial instruments, also known as financial securities or assets, are the contracts that represent a monetary claim or value. They are the 'products' of the financial system. Examples include equity (stocks), debt (bonds, loans, mortgages), and derivatives (options, futures). These instruments allow individuals and organizations to save, invest, borrow, and manage risk.

Financial regulators are governmental or quasi-governmental bodies responsible for overseeing and regulating the financial industry. Their primary objectives include protecting consumers and investors, ensuring the stability and integrity of financial markets, and preventing financial crime. Examples include central banks (like the Federal Reserve or the European Central Bank), securities commissions (like the SEC), and banking supervisors. They set capital requirements, conduct audits, and enforce compliance with laws and regulations.