兩者都是 Zero Coupon Bond 所得到的不同期 Yield，並繪製成 Spot Rate Curve 或是 Zero Curve

The spot yield curve is also known as the spot curve or the spot rate curve or the zero coupon yield curve or simply as the yield curve.

Spot rates are the market discounts for a single payment to be received in the future.  The discount rates for zero-coupon bonds are spot rates and we sometimes refer to spot rates as zero-coupon rates or simply zero rates.