Upanishads are commentaries by Upanishadic seers who have expounded their research on complex topics mentioned in the Vedas. Theories that are given in the Upanishad stand good for the theories holding philosophical truth about the cosmos.
Upanishads helps in constructing of the society. The teachings of Upanishads are at a glance based on three parameters - Atman, Brahman and the relation between the two. It may be further divided into Aakasha, Praana, Aksharaa, Jal, Agni etc...
One, who keeps on sticking to the materialistic world, yields nothing fruitful in his life. He does not know the joy of sharing, giving, and performing his duties in the society – the most unseen factor in today’s world.
The second parameter is Brahman. Brahman is in which everything in this universe starts and everything in which it ends. There is no supremacy than the Brahman and the Universe is the Brahman itself, universe was given birth from the Brahman. Brahman gives the relation of life with physical matters, visible or invisible. Everything which is build has to be destroyed someday in the Brahman itself, nothing is immortal.
The third parameter is relation of Brahman with the Universe. As stated above, Brahman constitutes everything in itself, so Atman is also a part of the Brahman. Brahman resides in us and we reside in the Brahman.
Hence, the Upanishads are derived from the Vedas and are the teachings which help in distinguishing between real and fake. The central theme of Upanishad revolves around ‘Ishavasyam’, which means the supremacy of Lord, and how he controls us and the nature. Pleasing and having internal devotion towards God will save us from all the calamities in our day to day life, be it with our family or brought by nature.
The Upanishads also helps us in having control on our mind and how to tackle ourselves in odd situations and it actually helps in controlling all are six senses. Discoveries made by the modern world were already revealed in the Upanishads long time ago.