A "poster child" is a term used to describe someone who represents or symbolizes an idea, cause, or group through their actions, characteristics, or experiences. The phrase originated in the 1940s when the March of Dimes charitable organization used photographs of children with polio on posters as a way to raise awareness and encourage donations for research and treatment of the disease. Since then, the term "poster child" has come to be used more broadly to refer to anyone who serves as an example or representative of something else.