The present value of a bond P as discounted value of future cash flows:
Ct = c*F, where c = coupon rate and F = face value
At expiration we have CT = cF+F
When the coupon rate c = y, the present value of the bond equal to the face value. The bond is call a “par bond”.
If c > y P > F. The bond is called a “premium bond”.
If c < y P < F. The bond is called a “discounted bond”.