I am not a hardware person! In my old German class we were discussing how some people have problems learning about new computer technology. I was not sympathetic, and my view was that they were just being lazy, and people should be FORCED to learn about twitter and facebook.
I was humiliated to find that some hardware is too complicated for me. Most tins now come with a pull off top, but sometimes a tin opener is still required. The two in my flat didn't work very well. I understood how they work, but they wouldn't open any cans, unless there was a huge amount of swearing and the tin being battered to death.
So I got a new tin opener -- the one with the white handle. It has some fancy design, but I am not sure how to open a can with it. It is a problem with geometry. I am not sure which way the can opener is meant to attach to the can.
I even searched on youtube for a tutorial....