Katherine Rooks remembers when she first learned that a punctuation mark could wield a lot of power.
The Denver-based writer had sent her high school-aged son a text message about logistics — coming home from school.
"I could tell from his response that he was agitated all of a sudden in our thread. And when he came home, he walked in the door and he came over and he said, 'What did you mean by this?' "
Rooks was confused. How could an innocuous text message send confusion?