Curio
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History

How we ended up here rather than somewhere else.

History

Why do some countries drive on the left?

Left was the older custom across much of the world, and the countries that changed did so because of specific historical pressures — mainly Napoleon, and later the pull of neighbours and American vehicles.

5 min read
History

Why do we have leap years?

A year is not a whole number of days, so the calendar has to be given an extra day now and then or the seasons slowly drift away from the dates.

5 min read
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Curio indexes questions, not pages. Every card is synthesised from multiple sources and shows its confidence.

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