The ball point pen was invented as the Second World War was about to begin in 1938

Biro's first idea for the ball point pen was to use the quick-dry newspaper ink in a fountain pen

The pen is still called a biro in countries including the UK, Ireland, Australia and Italy

On average, a pen can write approximately 45,000 words

The most expensive pen, inscribed in the Guiness Book of Records, worth one million euro is the platinum pen "Montegrappa"

In World War II, Air Force pilots used ballpoint pens because they did not leak at high altitudes.

Each year, choking on pen caps kills 100 people.

An average of 125 ball point pens are sold globally every second.