The problem with electronics (compared to mechanical items) is that you can't see how things work, or move. I remember in high school, we had some motors and turbines cut offs (or whatever they're called) to see how things move or work inside... kinda like those anatomy mannequins that you can take off the pieces. How do you explain how an iPod works? or why does the cursor on your screen moves? (probably to navigate away from this blog) Well, I found the answer looking at one of my former student's blog.