Par value refers to the price of a bond at its maturity. Bonds are traded or denominated in units of $1,000; however, they are quoted on the open market by dividing the base unit by 10. Therefore, a bond price of 100 refers to par. Bonds are commonly quoted on the open market in the following manner; 100:00. The digits to the right reflect pricing in (1/32nds). For example, a price of 99:25 would represent a price of 99.78125, or 99 + 25/32. A bond which is priced below par is said to be selling at a discount to par while a bond selling above par is said to be trading at a premium to par.
As interest rates move lower, bond prices move higher to the point where the bond yield is equivalent to the market yields for a comparable bond. In essence, when you purchase a premium bond, you are receiving a higher coupon over the life of the bond. However, you will receive par value at maturity.