The Upanishads (also commonly known as the Vedanta) are a collection of ancient Sanskrit texts of religious and philosophical subjects. There are many concepts that are central to Hinduism and related to Buddhism, Sikhism, and Jainism. They are also interpreted to be the highest purpose of the Veda. There are over two hundred Upanishads that are known, but the first fourteen are the oldest and the most important. At first, they were memorized and passed down orally. The oldest ones predate Buddhism, coming from before the 6th century BCE, and the newest ones are composed around and after the 15th century CE.
The first Upanishads helped shape religious and cultural ideas in ancient India, and helped transition people from Vedic ritualism to new ideas and practices. The first few Upanishads are considered Hindu scriptures, which centralize on Brahman, which is ultimate reality, and Atman, which is the soul and one’s self. When the Upanishads were translated in the 1800s, Western philosophers and other people who read these religious texts were impressed by them and regarded them highly, and even today the fundamental concepts between the Upanishads and western philosophy are still similar.