Stuff you can't live without.
Me: You see, we wrote e-mail on these large screens that sat on desks...
Kid: You mean like tablets?
Me: No, computers were bigger. They had keyboards, you couldn't touch the screens and often you needed a cart to move them around.
Kid: Why didn't you write on your phone? You had smartphones, right?
Kid: The phones could surf the web, play videos and games?
Kid: So what was the computer for?