VMware Player may execute a completely virtual PC independently from your PC. It is a program that has its own PC and its own operative system, and everything it has is independent. It is ideal to try new operative systems.
From VMware Player you may surf the Web, share folders, copy and paste data among your PC and a virtual one. One characteristic to mention is the possibility of determining the quantity of memory you need to have in your virtual PC, but this quantity will be discounted from the real available memory.