My dad spent his career as a customer service engineer for IBM. When I was about seven years old, back in the '70s, he took me to work at one of his accounts, the Washington Post. He showed me their room full of mainframe, and opened up a cabinet of core memory, thousands of wires and tiny donuts. Now and then, when I use a thumb drive with hundreds of billions of stored bits, I think of the day when I could see every individual bit in a box almost as big as I was.