Treasury Securities are debt instruments issued by the U.S. federal government to finance its operations and are considered among the safest investments in the world, backed by the full faith and credit of the United States. They come in three main forms: Treasury Bills (T-Bills) mature in one year or less and are sold at a discount; Treasury Notes (T-Notes) mature in 2–10 years and pay semi-annual interest; Treasury Bonds (T-Bonds) mature in 20–30 years and also pay semi-annual interest. Treasury securities are exempt from state and local taxes and are available directly from the U.S. government at TreasuryDirect.gov.