Over the years, mattresses using memory foam have become known as “memory foam mattresses”. But I’ve found that there is a lot of confusion over what exactly this means.
What this doesn’t mean, to many people’s surprise, is that the mattress is made completely or even mainly of memory foam.
Instead, memory foam mattresses typically have a basic “core” of standard polyurethane foam (often 5 – 6″ thick) that serves as the support layers of the mattress. And then on top of this is put layers of memory foam (from 2″ to 4+”, depending on the feel the mattress manufacturer is going for).
