Let me ask you a question:
Would you give someone $40,000 today to receive $40,000 back in 10 years?
I imagine that your answer is most likely NO. Why not? There are probably a number of reasons.
A bond is a liability companies use when a large amount of cash is needed. Rather than go to a bank or other lender, a company will issue bonds and sell them to the public. By selling bonds on the open