Bonds are one of the safest investments in the market. Returns are good and investments don't require much. There are four types of bonds. Government, corporate, state and local, and foreign government bonds. One of the most great situations about bonds is the fact that you can gain your initial investment back. This is great for beginning investors, and/or for those who are more conservative.
The US Government sells what they call Treasury Bonds through the Treasury Department. You can always purchase a treasury with Mature dates that range between three months to thirty years. The government have T-notes, Treasury Bills. These bonds are all backed behind the US Government, and tax is only charged on the interest that the bonds earn.
You can find corporate investments through public securities market. A corporate is selling their debt to you. They have high interest rates, but they are very risky. If the company falls, the bond is worth nothing. State and local Governments also sell bonds. The federal government bonds have higher interest because they don't go bankrupt like the state and local government. State and Local Government investment are income tax free, including on interest. Taxes on the state and local level will be waived. The most common bond is municipal bonds.
Foreign bonds are actually difficult to purchase, and is often considered to be apart of a mutual fund. Foreign bonds are the riskiest of them all. However, the safest investment that you can make is one that is issued be US Government.