Colors don't exist. The sky is not blue. The grass is not green. A violet is not even violet. But color still plays an important role in our lives. Color can be a signal, as in a traffic light. It can be a call for help, like a life jacket. It can help us stand out or blend in, or feel like part of a team. Colors even affect our mood: red can make us angry, blue can make us sad, and yellow can brighten our day. Young readers will never look at color the same way again.