Big ole pool of very fast ram that can be accessed by the CPU and GPU. Lets you run larger models. AMD does the same thing with Strix Halo. I have a 128gb machine at home, and have had difficulties running 120b models, but 70b and below run pretty well.

Yep, exactly. It's just one shared pool of RAM with zero-copies necessary.

In best case its also on-chip high speed ram.