I'm almost there thanks to your information (and encouragement)
The only thing that I still don't quite understand is: assuming the 2 wires out from a socket are like the 2 wires coming from an alternator: why if I touch one of them I receive an electrical shock, but the same doesn't happen if a touch the other one? I understand why I receive a shok if a touch both (closed circuit). It seems like both wires in AC should be exactely the same.
Thanks one again.
[This message has been edited by Joaqu'n (edited 24 May 2001).]