In article ,
Stormin Mormon wrote:

* the hot wire goes to the smaller slot in the
socket. Less likely to have foreign objects
stuck in the smaller slot. (Think kids with
metal objects.)

In about 1945 our milk was delivered to the house. The milk bottle had
a paper cover held in place by a wire. I was about five hears old, and
knew there was electricity in the outlet, and wire conducted
electricity. One morning I took the morning's milk wire and poked its
two ends into an outlet. The wire exploded and burned my fingers. I
think I had a "Near-Darwin" experience!

My parents built the house in 1942, and original outlets had silver and
copper sides. There was no ground terminal, but the silver side had a
wider slot. I think the silver-copper convention may go back to the
introduction of that style AC connector.

Fred