I had a process that had a Mem Usage of 685,520 K and PF usage of 2.06 GB. I end the process and my PF usage drops to 1.17 GB. That's a ~890,000 K difference - not ~685,000 K. My question is... why the difference? Why does ending this process free more RAM than the process was taking up? Is this what's known as a memory leak?