Who is Leonardo da Vinci? What makes him great upon face of man?

Leonardo di ser Piero da Vinci was an Italian polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist and writer.
e is widely considered to be one of the greatest painters of all time and perhaps the most diversely talented person ever to have lived.
Leonardo was and is renowned^[2] primarily as a painter. Among his works, the Mona Lisa is most famous and most parodied portrait and The Last Supper the most reproduced religious painting of all time, with their fame approached only by Michelangelo's Creation of Adam.^[1] Leonardo's drawing of the Vitruvian Man is also regarded as a cultural icon,^[4] being reproduced on everything from the euro to text books to t-shirts. Perhaps fifteen of his paintings survive, the small number due to his constant, and frequently disastrous, experimentation with new techniques, and his chronic procrastination
Among the works created by Leonardo in the 16th century is the small portrait known as the Mona Lisa or "la Gioconda", the laughing one. In the present era it is arguably the most famous painting in the world. Its fame rests, in particular, on the elusive smile on the woman's face, its mysterious quality brought about perhaps by the fact that the artist has subtly shadowed the corners of the mouth and eyes so that the exact nature of the smile cannot be determined. The shadowy quality for which the work is renowned came to be called "sfumato" or Leonardo's smoke. Vasari, who is generally thought to have known the painting only by repute, said that "the smile was so pleasing that it seemed divine rather than human; and those who saw it were amazed to find that it was as alive as the original".
Leonardo's approach to science was an observational one: he tried to understand a phenomenon by describing and depicting it in utmost detail, and did not emphasize experiments or theoretical explanation.