answer:Just to clear up any confusion, in North America, plugs made recently (seems to be within the last 30 years or so) have one prong that is larger than the other, making it impossible to plug something in upside down. Also, some plugs have a grounding prong that requires a socket with 3 holes rather than two. Older plugs have two prongs of the same size, but it doesn’t seem to matter whether you insert them “right side up” or not. I’m not an expert by any means, so please excuse my (lack of) terminology :)