Existentialism is a philosophical movement that focuses on individual existence, freedom, and choice. It emphasizes the idea that people create their own meaning and purpose in life, rather than relying on external sources such as religion or societal norms. Key figures in this movement include Jean-Paul Sartre, Simone de Beauvoir, and Friedrich Nietzsche. Existentialists believe that life is inherently absurd and that individuals must confront this absurdity to find their own path. This philosophy often explores themes of anxiety, despair, and authenticity, encouraging people to take responsibility for their actions and embrace their freedom in an uncertain world.