The document discusses the history and recent developments in deep learning. It outlines several important events in the field including early neural networks in the 1940s-50s, the introduction of backpropagation in the 1960s-80s, and recent advances that have enabled deep learning to be applied successfully to complex real-world problems in areas like computer vision, natural language processing, and game playing. These recent applications and advances are enabling deep learning to be applied to an increasingly wide range of domains.