Treasury Bills, often referred to as T-Bills, are short-term government securities issued by the U.S. Department of the Treasury. They are sold at a discount to their face value and mature in a year or less, making them a low-risk investment option. Investors receive the face value upon maturity, with the difference between the purchase price and the face value representing the interest earned. T-Bills are popular among investors seeking a safe place to park their money, as they are backed by the full faith and credit of the U.S. government. They are typically issued in various maturities, such as 4, 8, 13, 26, and 52 weeks, providing flexibility for different investment strategies.