Tae Kwon Do is only around 60 years old.
64
It's impossible to kill yourself by holding your breath.
703
Only 8% of the world’s currency is physical money. The rest exists only on computers.
20
Author J K Rowling wrote the final chapter of the last Harry Potter book in "something like 1990", seven years before the release of the first book.
7
A pipe 2 feet in diameter will allow four times more fluid to pass through it than a pipe 1 foot in diameter.
20
Not swinging your arms when you walk increases the effort of walking by 12%, the equivalent of walking 20% faster or carrying a 10 kg backpack.
12
The Pittsburgh Steelers were originally called the Pirates.
50