I once saw a T-shirt that said "Great art isn't supposed to match your sofa." To many, perhaps the majority (?) art is about looking good, and if that is what it means to you, than great, go out and purchase that Bob Ross. But truly good Art is supposed to touch people on a higher plane. It is supposed to reach them on a personal, emotional level and really move them. It is subjective, relying on ones personal moods and Attitudes. It is philosophical, relating to the Nature of art, rather than on what is known in the mind, but distinct from itself. It is the substance that is essential, which can go far beyond what you see.
With the invention of the camera, many felt that paintings would become obsolete. The art world reacted to that by making paintings go beyond the mere Subject matter. Movements like Surrealism, Impressionism and Abstract came into popularity because camera's couldn't do what the artist could. (With the help of computers they now can, but that is entirely beside the point)
In a time of great painters Picasso stood out, he did what he was born to do. Apparently he struggled in school, as a child he was bad at Math because the 7's looked like upside down noses to him. He had trouble concentrating on things that weren't art because art was everything to him. Picasso had the rare distinction of being popular in his own lifetime as well as after his death. This popularity served him well. Mainly because he was a Prick. He was mean to his children, anti-feminist, and pro-Stalinist and the People loved him. He was a shameless self promoter and it worked for him.
Picasso evolved as a painter, going through several periods. This is why his paintings remain so valuable despite the fact that he painted thousands of them. His Blue Period was somber and gloomy. Haunted by melancholy and Despair. He would paint starving people, whores and the homeless. Blindness was another common theme during this period. Check out The Blind Man's Meal or Celestina.
Perhaps as a reaction to his Blue Period his Rose Period was a lot less depressing. He began using less depressing subject matter and happier colors. Lady with a Fan, Two Youths, Harlequin Family, and Boy with a Dog were from this period and Stand out really well.
After the Rose Period, he went through his African Period obviously based on African art. It is an early segue into Cubism. One of his more famous paintings, Les Demoiselles d'Avignon comes from this period. Les Demoiselles d'Avignon is a controversial work of five naked Prostitutes in Barcelona. NOne of them are very feminine or even pretty. They are instead very angular and uneven.
Picasso is probably best known for Cubism. His name seems synonymous with this movement. It was created by Picasso and Braque and its influence went so far as to touch music and literature. In Cubism, the artist takes the subject, destroys it and then reassembles it so that it can be viewed from different angles. This gives it a much greater Depth and range. From this movement spawned Analytical Cubism and Synthetic Cubism. Analytical Cubism analyzed objects and brought them back to their basic shapes. Cezanne was a major influence to this form of Cubism. Synthetic Cubism on the other hand introduced different textures, and even objects onto paintings. Newspaper being one of the most common. Picasso, Braque and Juan Gris developed this movement between 1912 and 1919.
Classicism and surrealism was his last real movement. Picasso’s most famous work is from this perieod, Guernica. This is the embodimentof the the inhumanity, brutality and hopelessness of war. His pacifism showing in this painting, it was the reaction to the bombing of Guernica in 1937. It is a very deep painting that shows how the innocent bystanders are those who hurt the most in war. This painting helped bring the Spanish Civil war to the rest of the worlds conscious. I'm not going to bother with the various interpretations of the painting, that deserves its own review, but it is very Profound painting and deserves more than just a cursory glance.
His final works could not be constrained to any Movement, and many people had no interest in them. After he died, however, people discovered that Picasso invented Neo-expressionism. They just didn't know it at the time. He has painted thousands of paintings, many of them some of the most valuable in the world. Maybe his greatest achievement is not his works, maybe it is him. Whether you love the guy or hate him, you know him.
"Every child is an artist. The problem is how to remain an artist once we grow up."
~Pablo Picasso