The boys had been up in the attic together helping with some cleaning. The kids uncovered an old manual typewriter and asked her, "Hey, Mom, what's this?"
"Oh, that's an old typewriter," she answered, thinking that would satisfy their curiosity.
"Well, what does it do?" they queried.
"I'll show you," their mother said. She went downstairs and returned with a blank piece of paper. She rolled the paper into the typewriter and began striking the keys, leaving black letters of print on the page.
"WOW!" the boys exclaimed, "That's really cool -- but how does it work like that? Where do you plug it in?"
"There is no plug," she answered. "It doesn't need a plug."
"Then where do you put the batteries?" they persisted.
"It doesn't need batteries either," she continued.
"Wow! This is so cool!" the brothers exclaimed. "Someone should have invented this a long time ago!"