Let's start with credit unions, which are supervised by the National Credit Union Administration (NCUA). Created in 1970, the NCUA charters, supervises, regulates, and provides as much as $250,000 in deposit insurance to "millions of account holders in all federal credit unions and the overwhelming majority of state-chartered credit unions."
Next, FDIC insurance is only for cash deposits. Other financial instruments that are not cash -- like stocks, bonds, mutual funds, annuities, cryptocurrencies, and others -- are ineligible for insurance.