The Upanishads form a part of the Vedas and are essentially a set of ancient mystic teachings and imparting of knowledge. The term Upanishad has been derived from three words: "Upa" (near), Ni (down) and shad (to sit), i.e., sitting down near. During ancient times, pupils used to sit near the teacher in a circle to learn the holy teachings and sacred scriptures. The Upanishad philosophy basically indicates learning from a spiritual teacher. The exact number of classical Upanishads is not known. Scholars differ when it comes to estimating the number of Upanishads that exist. It is estimated that there are around 350 Upanishads that exist today.
The Upanishads provide us with spiritual knowledge and philosophical
reasoning. Upanishads aim at attaining a level of understanding beyond
ordinary knowledge about living. They aim at seeking a higher level of
understanding about survival. They seek to create awareness about our
purpose in life. They dwell on the psychology of the human mind. They
speak about consciousness, sub-consciousness and dreams. They go beyond
ordinary knowing and aim at a higher level of realization.
The Upanishads also contain information on the divine power of the word "Aum".
This word is said to have cosmic vibrations and is said to underlie all
forms of existence and trinity principles. For creating sound, one needs
to have atleast two things that strike against each other. But Aum is
one sound that is created without any help or friction. Thus, this is
the sound of the Universe, the vibrations that you feel inside when you
close your ears. The Upanishads aim at making our lives more meaningful
by making us realize the importance of self-realization that goes a long
way into shaping the kind of individual we become.