I used to design real-time software/ hardware back in the 1970s- 1980s.  Mostly assembler. Got out of engineering as a profession in 1980 but still tinker with real-time microcontrollers such as the Wilke Technologies Tiny Tiger. So my level of skill is that of one who understands machines at low levels fairly well but don't really know the high level stuff that well. I just barely know enough to get VMware to let me run XP and Linux on my Vista x64 machine.