It looks like we both have been leading a sheltered life. We are both right: See
https://ux.stackexchange.com/questions/36207/which-way-should-be-on-for-a-switch
Thanks for bring this to my attention. It's a Country-specific thing.
Having dealt with non-English speaking people, I now know what a "plug point" is. In the US, we call them electrical outlets. It also wasn't a common word I learned in German either. German and English is kinda close if it wasn't for all of those pronouns without any rhyme or reason for masculine, feminine or neuter.
I digress.
I wish that the curriculum would have been focused on scientific or traveling. e.g words for Taxi, bus, rest area and bathroom were never discussed. The boot (what we call the trunk) of a car was discussed. For Brittish, s, z's and c's get messed up. I know I use grey and gray interchangeably.
100 VAC (Japan) and 277 (US lighting in some 3 phase buildings ) threw me for a while too. We had some Japanease equipment that operated off of 100V. Fraunhoffer (a German outfit) shared some space in our building when they were doing research on Aluminum foam. Since they were using furnaces from Germany, they got a German distribution system which, I think was mainly 240. We were 120/208/277 single phase, 208 three phase and 460 three-phase.
We moved from a 240 V environment. Most of the stuff worked with tap changes except the diffusion pumps (1100 W). The heaters were eventually changed to 208V. The 460 was used for the HVAC system which was about 36 air to water heat pumps.