روز بین المللی چپ دستتقویم علمی ایران

International Left Handers Day is an international day observed annually on August 13 to celebrate the uniqueness and differences of the left handers.

International Left Hander's Day was created to celebrate sinistrality and raise awareness of the advantages and disadvantages of being left-handed in a predominantly right-handed world. It celebrates left-handed people’s uniqueness and differences, a subset of humanity comprising seven to ten percent of the world's population.[citation needed] The day also spread awareness on issues faced by left-handers e.g. the importance of the special needs for left-handed children, and the likelihood for left-handers to develop schizophrenia. There are approximately 708 million left-handed people in the world. Men are more likely to be left handed than women.