Between 1908-1918 Picasso's Cubism period evoked new molding of art entirely. It used geometric and abstract styles that challenged the expectations of the standards. It was created with Georges Braque, A french painter that contributed to the project.
1918-1945 Was Picasso's Classicism and Surrealism Period. During this time WW1 is current and has sent Picasso into a state of wanting to end it. He creates pieces that give a somber tone mixed with the message of anti-war.
Overall Picasso Gave the art world the gift of free expression without the traditional barriers that used to be mandatory. He used his art to express the world of its greed and anger that he felt was hidden under the brush.