President Barack Obama signing with his left hand

The above photo by Pete Souza, American photojournalist and the current chief White House photographer for President Barack Obama, shows Obama signing at his desk in the Oval Office with his left hand on 3 March 2009. Left-handedness is the natural preference for the left hand over the right for everyday activities such as writing, a habit found in about seven to ten per cent of the population of the world. Leonardo da Vinci was a left-handed person who used to not only write with his left hand, but he used to write in mirror-image, a practice that was criticized by his detractors who opined that he used mirror image writing to keep his notes and journals secretive. But the fact is that it was easier for Leonardo to write in mirror image than the usual writing, because he was left-handed.