The Upanishads teach that the ultimate goal of human existence is to attain moksha, or liberation from the cycle of birth, death, and rebirth.

The atman is the individual soul, which is believed to be eternal and unchanging. It is distinct from the body and the mind, and it is the essence of what makes a person who they are.

Brahman is the universal soul, which is believed to be the source of all existence. It is infinite, eternal, and unchanging, and it is the ultimate reality.

According to the Upanishads, atman and Brahman are ultimately the same. This is expressed in the famous phrase, (\text{aham brahma asmi}), which means (\text{I am Brahman}).

Samsara is the process of rebirth, in which the soul is repeatedly born into different bodies until it attains moksha.

The law of karma is the belief that every action has a corresponding reaction. This means that the actions we perform in this life will determine our fate in the next life.

Dharma is the path of righteousness, which is believed to lead to moksha. It is the opposite of adharma, which is the path of unrighteousness.

The goal of the yogi is to attain moksha, or liberation from the cycle of birth, death, and rebirth.

The four paths of yoga are bhakti yoga (the path of devotion), karma yoga (the path of action), jnana yoga (the path of knowledge), and raja yoga (the path of meditation).

The ultimate goal of bhakti yoga is to experience divine love, which is believed to be the highest form of happiness.

The ultimate goal of karma yoga is to serve others without expecting anything in return.

The ultimate goal of jnana yoga is to attain moksha, or liberation from the cycle of birth, death, and rebirth.

The ultimate goal of raja yoga is to attain moksha, or liberation from the cycle of birth, death, and rebirth.

Maya is the illusion of the world, which is believed to be created by the mind. It is the opposite of brahman, which is the ultimate reality.

Avidya is the ignorance of the true nature of reality, which is believed to be the cause of suffering. It is the opposite of vidya, which is the knowledge of the true nature of reality.