You most likely know what a savings bond is. However, do you know why it is a good idea to purchase one? There are many great benefits to buying and holding on to your savings bonds for as long as possible.The Bonds Earn InterestEach savings bond that you purchase will earn interest on a quarterly basis. When the economy is doing well, you can expect an interest rate of as much as five percent. If the economy is doing poorly, you will still accrue interest on the bond. Fortunately, the interest rate on a savings bond is variable if purchased between 1997 and 2005. This means that the amount of interest paid is dependent on current conditions regardless of when it was purchased.They Are Purchased At A DiscountSavings bonds are purchased at less than face value. This means that a $50 savings bond is generally purchased for only $25. The only downside is that your bond would only be worth $25 when your purchase it. You would then have to wait several years until the bond matures for it to be worth face value.Savings Bonds Are A Safe InvestmentLike other government notes, a savings bond is a safe investment that will give you a steady and predictable return. Therefore, you can rest assured that your money is going to be there when you want to redeem your bond. After you cash your bond, you can use if for any purpose. However, keep in mind that you will be subjected to income tax on any bond that is cashed in.Buying a savings bond will help you save for the future while also helping the government raise money to pay its bills. They are a safe investment that can help you pay for college, save for a home or help you meet a myriad of other future financial goals.