Difference between Market Discount Rate and Yield-To-Maturity

Can anyone tell me what is the exact difference between Market Discount Rate and Yield-To-Maturity, based on the examples shared here? I feel they are the same here.

Thanks!

Looks the same to me too. They even say the YTM is an implied market discount rate. :+1:

Yeah, but then why two different terms for the same thing? I mean, how do the two situations differ? I think I am missing something here.