Treasuries are government debt securities issued by the U.S. Department of the Treasury to finance national spending. They come in various forms, including Treasury bills (short-term), Treasury notes (medium-term), and Treasury bonds (long-term). Investors purchase these securities, effectively lending money to the government in exchange for periodic interest payments and the return of the principal at maturity. Treasuries are considered one of the safest investments because they are backed by the full faith and credit of the U.S. government. They play a crucial role in the financial system, serving as a benchmark for other interest rates and providing liquidity in the market.