The term Impressionism originated from Claude Monet's painting Sunrise (1873), which was criticized for its unfinished and lack of detailed style. Impressionist artists worked outdoors capturing transient effects of light and color through loose brushstrokes rather than blending tones. They aimed to depict visual impressions rather than tell stories. Key Impressionist artists included Monet, Renoir, Morisot, Degas, Pissarro, Cassatt, and Sisley who applied this revolutionary approach in the late 19th century.