Can you provide a summary of Sartre's "Being and Nothingness"?

"Being and Nothingness" by Jean-Paul Sartre explores the concept of existentialism, focusing on the idea that individuals create their own essence through their choices and actions. Sartre argues that human existence is characterized by freedom and responsibility, and that individuals must confront the inherent meaninglessness of life. The book delves into themes of consciousness, authenticity, and the struggle to find meaning in a world devoid of inherent purpose.