PC (Personal Computer) is a system, consisting of many components. Some  of those components, like Windows XP, and all your other programs, are software.  The stuff you can actually see and touch, and would likely break if you threw it  out a fifth-story window, is hardware.
 
 Not everybody has exactly the same hardware. But those of you who have a desktop  system, like the example shown in Figure 1, probably have most of the components  shown in that same figure. Those of you with notebook computers probably have  most of the same components. Only in your case the components are all integrated  into a single book-sized portable unit.
 
