SortStack #191 — 2026-12-17

By year · Order from earliest to most recent.

1. Constantinople falls to the Ottoman army of Mehmed the Conqueror 1453

   The Ottomans breached walls that had stood for a thousand years using enormous cannons — built by Orban, a Hungarian engineer who had first offered his services to the Byzantines.

2. The Penny Black, the world's first postage stamp, goes on sale 1840

   It bore Queen Victoria's profile and no country name — and because Britain invented the stamp, British stamps still omit the country's name today.

3. The Wright brothers achieve the first powered airplane flight 1903

   The first flight lasted twelve seconds and covered about 37 meters — shorter than the wingspan of a modern jumbo jet.

4. President John F. Kennedy is assassinated in Dallas 1963

   Abraham Zapruder's 26-second home movie of the motorcade became one of the most studied pieces of film ever shot.

5. Pac-Man arrives in arcades 1980

   Designer Toru Iwatani said the shape was inspired by a pizza with a slice missing. The game was renamed from 'Puck Man' to deter vandals altering the P.

6. DeepMind's AlphaGo defeats Go champion Lee Sedol 2016

   AlphaGo's 'Move 37' was so alien that commentators assumed it was a mistake. Lee won a single game back with a move fans dubbed 'God's touch.'

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