π maximally simplifies finding the circumference of of a circle from its diameter
More importantly, π is the area of the unit circle. If you're talking about angles you want τ (tau), if you're talking about area you want π. And you always want pie, ha ha.
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
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