How is a ballpoint pen made?

The ballpoint pen was invented in the 1940s by the Hungarian Lazlo Biro who, while watching a ball roll during a game, had the intuition of sliding a ball at the end of the pen which, passing on the sheet, released the right amount of ink to allow a fluid and flowing writing. The mechanism that makes the ink exit is a “rotating” one for high range pens and a “snap” one for medium-low range pens. The ballpoint pen uses oil-based inks, which are denser and quicker to dry. The refill generally has an average duration of 6 months and can write up to 12-13 km.