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What do the terms par value, purchase price, call price, call date, and coupon rate mean in the context of bonds?
Bonds are valued based on all of this, using the concept of the "time value of money". Simply stated, money now is worth more than money later, because of what you can do with money between now and later. Case in point: let's say the par value of a bond is $100, and will mature 10 years from this date (these are common terms for most bonds, though the U.S. Treasury has a variety of bonds with varying par values and maturation periods), with a 0% coupon rate (nothing's paid out prior to maturity). If the company or government issuing the bonds needs one million dollars, and the people buying the bonds are expecting a 5% rate of return on their investment, then each bond would only sell for about $62, and the bond issuer would have to sell a par value of $1.62 million in bonds to get its $1m now. These numbers are based on equations that calculate the "future value" of an investment made now, and conversely the "present value" of a future return. Back to that time value of money concept, money now (that you're paying to buy the bond) is worth more than money later (that you'll get back at maturity), so you will expect to be returned more than you invested to account for this time difference. The percentage of rate of return is known as the "yield" or the "discount rate" depending on what you're calculating, what else you take into consideration when defining the rate (like inflation), and whom you talk to. Now, that $1.62m in par value may be hard for the bond issuer to swallow. The issuer is effectively paying interest on interest over the lifetime of the bond. Instead, many issuers choose to issue "coupon bonds", which have a "coupon rate" determining the amount of a "coupon payment". This can be equated pretty closely with you making interest-only payments on a credit card balance; each period in which interest is compounded, you pay the amount of interest that has accrued, to avoid this compounding effect.  From an accounting standpoint, the coupon rate lowers the amount of real monies paid; the same $1m in bonds, maturing in 10 years with a 5% expected rate of return, but with a 5% coupon rate, now only requires payments totalling $1.5m, and that half-million in interest is paid $50k at a time annually (or $25k semi-annually). But, from a finance standpoint, because the payments made in the first few years are worth more than the payments made closer to and at maturity, the present value of all these coupon payments (plus the maturity payout) is higher than if the full payout happened at maturity, and so the future value of the total investment is higher.  Coupon rates on bonds thus allow a bond issuer to plan a bond package in less complicated terms. If you as a small business need $1m for a project, which you will repay in 10 years, and during that time you are willing to tolerate a 5% interest rate on the outstanding money, then that's exactly how you issue the bonds; $1 million worth, to mature in 10 years and a 5% coupon rate. Now, whether the market is willing to accept that rate is up to the market. Right now, they'd be over the moon with that rate, and would be willing to buy the bonds for more than their face value, because the present value would then match the yield they're willing to accept (as in any market system, you as the seller will sell to the highest bidder to get the best price available). If however, they think you are a bad bet, they'll want an even higher rate of return, and so the present value of all coupon and maturity payments will be less than the par value, and so will the purchase price.