Original: In 1900, Baum and Denslow (with whom he shared the copyright) published The Wonderful Wizard of Oz to much critical acclaim and financial success.
Simplified: After several successes in the late 1890s, Baum published what he called an "American fairy tale," The Wonderful Wizard of Oz, in 1900. The book had pictures drawn by the American artist W. W. Denslow.