I sat next to a woman at a meeting the recently who lives in New Brunswick, in the Canadian Maritimes. She started a list of words that are pronounced differently in Canada and the United States, and words that are spelled differently. Words like tire/tyre. She said when she first started traveling to the USA for meetings, the pronunciation differences really threw her off.
One of the joys of travel, is learning how common things are different. Sometimes it is differences in a shared language. Sometimes it is common objects, electrical current, electrical connections. My travel bag has adaptors and power cords for things that work on universal power (110-120-220-230.) I often have to get out the jewelers loupe (magnifier) to read the fine print on a computer power supply to see if it works on multiple power levels (most do.)
I was surprised by the shape of the fire hydrants in Reykjavik. Not that they are all the same around the world, but these seemed skinny, probably made to fit a particular set of engineering needs.
Routine things, that are different