Explore Leonardo da Vinci's most famous works like the Mona Lisa, as well as his drawings and unfinished works. In 1517, Leonardo showed a visitor a portrait of Lisa del Giocondo, the wife of a ...

“[One] who works with the door open gets all kinds of interruptions, but [they] also occasionally gets clues as to what the world is and what might be important.” — Richard Hamming Quartz is a set of ...