Why Every Country Has a Different Plug
The history of the voltage split is a pretty short story, and one you've probably heard bits and pieces of before. Edison's early experiments with direct current (DC) power in the late 1800s netted the first useful mainstream applications for electricity, but suffered from a tendency to lose voltage over long distances.
Nonetheless, when Nikola Tesla invented a means of long-distance transmission with alternating current (AC) power, he was doing so in direct competition with Edison's technology, which happened to be 110v. He stuck with that. By the time people started to realize that 240v power might not be such a bad idea for the US, it was the 1950s, and switching was out of the question.
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