Pablo Picasso was a Spanish painter and sculptor who spent most of his adult life in France. He is regarded as one of the most influential artists of the 20th century, most famous for co-founding the Cubist movement. Cubism revolutionized European painting by breaking objects and figures into geometric shapes and showing them from multiple viewpoints simultaneously. Picasso’s career was marked by distinct periods, including the Blue Period, the Rose Period, and his African-influenced period. One of his most powerful works, 'Guernica,' is a massive mural depicting the horrors of the Spanish Civil War and has become a universal symbol of anti-war sentiment. His prolific output and constant stylistic reinvention transformed the definition of modern art, influencing everything from graphic design to architecture.