You will be surprised to know that the inventor of Uno invested 8,000 dollars in its creation only to get back 5,000 dollars when it went on sale, and that finally, years later he sold it to Mattel for 50,000 dollars. To this day, Uno's sales continue to grow year after year and more than 50 versions of the game have been released. In addition, Uno is considered to help develop motor skills in early childhood education, as well as teaching color recognition and number recognition in a fun way. It also improves strategic skills and simple mathematical calculation.