Bonds are debt instruments that allow governments and corporations to borrow money from investors. Instead of taking loans from banks, they issue bonds where investors receive fixed interest payments until maturity, when the full amount is repaid. There are different types of bonds including government bonds, which are backed by the government and have lower risk, and corporate bonds, which are riskier but can offer higher returns. When choosing bonds, investors must consider factors like security, credit rating, risks involving interest rates and inflation.