What is the difference between iAd vs AdServices?

Hi. I'm having a hard time differentiating the iAd and AdServices frameworks. Is there a reason to use one framework over the other?

It appears that AdServices is iOS14+. Is iAd being deprecated?

I also noticed that iAd requires users to explicitly accept App Tracking in order to pull attribution data but AdServices does not. Is that true? Is it the same data?