Existentialism is a philosophical movement that emphasizes individual existence, freedom, and choice. It posits that individuals are responsible for creating their own meaning in a world that can often seem absurd or indifferent. Key figures in this movement include Jean-Paul Sartre and Simone de Beauvoir, who explored themes of authenticity and the human condition. At its core, existentialism challenges people to confront the inherent uncertainties of life and to embrace their freedom to make choices. This philosophy encourages self-reflection and personal responsibility, urging individuals to live authentically and to find their own path in a complex world.