Today, we use Braille not only to write words in all languages , but also to write math and music. Blind people send Braille greeting cards, wear Braille watches, type on Braille keyboards, and take elevators with Braille controls. Louis Braille had no idea how many people he had helped. On the door of the house where he was born are the words "He opened the doors of knowledge to all those who are cannot see.