These are certificates of time deposit at a commercial bank. The maturities are unlimited. There is a good secondary market. The rate is based on a yield basis. And it is based on actual days for a 360 day year.
Interest is paid at maturity.
These are notes of local agencies secured by a contract with federal agencies and by the pledge of the full faith and credit of the U.S. Government. They mature in periods of up to one year. There is a good secondary market for these. The rate is based on a yield basis. Interest is paid at maturity.