Theater of the Absurd:

Though Jarry's Ubu Roi pioneered absurdist theater in 1896, the movement flourished after World War II. Absurdist dramatists believed that the human condition is essentially absurd and that this condition can only be represented in theater that is itself absurd. They used surrealist and expressionist techniques blended with philosophical existentialism.

The Harper Handbook to Literature, Second Edition

Major Figures:
Eugene Ionesco
"Cut off from his religious, metaphysical, and transcendental roots, man is lost; all his actions become senseless, absurd, useless."
"People drowning in meaninglessness can only be grotesque, their sufferings can only appear tragic by derision.
Major works: Rhinoceros, The Bald Soprano, The Lesson
Samuel Beckett
Major works: Waiting For Godot (En attendant Godot), Endgame, Not I, Catastrophe, Quad, Happy Days
Albert Camus
Jean Paul Sartre

Fiction: Kafka