Money Market accounts have the advantage of being able to withdraw your money whenever you need it. CD or Certificate of Deposit accounts hold a little bit of a higher interest rate, however you have to wait until the term is up before you can withdraw your money (same with bonds). The money market account can give you higher returns where as other bonds, certificates give fixed and less interest. At the same time first one is not risk proof and you can lose money where as second options are fully secured.