If you search for the difference between EHR and EMR, you'll find other sites that answer this question.

Some sites will define EHR as holistic and EMR as a narrower view. Another way this is explained is that EHR is interoperable and portable, while EMR was built to be an institutional record, in a single practice.

I don't know if everyone who reads this difference sees the same thing that I see. It looks to me like a glossing over or an apologetic view of EMR. Engineers knew better than to build a siloed health record. EMR should never have been built. From conceptualization, every vendor should have been building for interoperability. We didn't need the internet to know that the information belongs to the patient. We had standardization techniques in the 18th century. Patient Health Information should never be tied to a particular system. It should have been built to be portable and this should be a core component of every system going forward.