What is Density-Based method?

C-H Kuo

This is a great place for post-school learning. I appreciate the large and diversified knowledge from this website.

I have been working on CFD several years, and once a while I hear people talking about pressure-based and density-based solution methods. I really don't know what it is, could not find from literature, and felt shame to ask. I asked several times and did not get it. I think it is an ambiguous term or the person I asked is same as me--don't really know it.

Could someone give a detailed description on this method, and the advantage and disadvantage of it. I will appreciate this, and I belive many out there will also appreciate it.