Inventions, firsts, and turning points tied to today’s date — each one sourced and dated.
On this day in 1954, schoolchildren in Pittsburgh rolled up their sleeves for Jonas Salk's new polio vaccine.
On this day in 1945, a photographer caught the second flag-raising on Mount Suribachi — and made an icon.
By tradition dated to this day in 1455, Europe's first major book printed with movable type rolled off the press.
