The Упанишады are ancient Indian texts that form the philosophical basis of Hinduism. They are part of the larger body of scriptures known as the Vedas and focus on spiritual knowledge and meditation. The texts explore concepts such as the nature of reality, the self, and the ultimate purpose of life. Composed between 800 and 400 BCE, the Упанишады emphasize the importance of personal experience and introspection in understanding the universe. They introduce key ideas like Brahman (the ultimate reality) and Atman (the individual soul), which are central to Hindu philosophy and spirituality.