Rank cities by population and plot the result. A handful of megacities tower on the left; thousands of towns form a long, whispering tail stretching to the right. Now do the same with word frequencies, website traffic, the energy released by earthquakes, or personal wealth. The shape is the same: steep drop, then a tail that refuses to die.
These are power-law distributions, and they emerge wherever success breeds success. A city that grows attracts more people, which makes it grow further. A word used often becomes even more familiar, so it gets used again. The rich get richer through mechanics, and only sometimes through merit.
The tail matters more than it looks. In a bell curve, extremes are vanishingly rare. In a power law, the single largest event can dwarf the rest combined. This is why one earthquake, one pandemic, or one black swan trade can reshape everything.
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