Going all the way back to the post-World War II “World of Tomorrow,” we were going to have telephones that incorporated a camera and a screen so a user could see the person on the other end of the line. Technologically, this was not a great reach 50 years ago. The big issue was demand. Nobody thought it sounded like a particularly good idea! People looked at their phone and looked in the mirror and said, No thanks. Besides, not so long ago all telephones were landlines, and a modestly affluent household had maybe three. What was the thrill of standing in one’s kitchen and talking to a friend standing in another kitchen? This reality never changed until the advent of ubiquitous cellular phones. My theory is, once phones became truly mobile and included cameras, there was a point to sharing an image. “Look! Me at Mt. Rushmore!” People, particularly young people, became comfortable with the idea of a visual telephone. Now we can’t get enough Facetime.