VEDANTA

Vedanta is made of two words - 1 - Veda = knowledge and 2 - ant = the end . so Vedanta= the end of knowledge ; the perfect knowledge ; there is no knoledge beyond that ; there can not be /is more knowledge than this ; the knowledge all that can be ; the knowledge that one could have as human being and should have .

Vedas are also called as Shruties = the knowledge that Heard by competent students from their scholar Gurus that were Realized Souls . Realized Souls = those who had unity with the Whole / Atma / Universal Soul .
Vedas are also called Srmities = the memory that has been maintained by those competent students who themselves grew to the level of their Gurus and passed on the same to their students some times more refined and mature and clear but some time with some deviations .
Upnishdas are Vedant , the perfect knowledge ; Dialogues between Guru and student both of the same and almost equal caliber , equal achievement and equal understanding .
Vedas are the source of all schools of Indian philosophies except one Charwak . Sankhya- Yoga , Nyay- Vaisheshik , Mimansa , varities of Vedanta , Baudhism in many forms and Janism in various sects , all these have their roots in Vedas .

Vedant (called Adwait Vedant =where there is One and no second ) is the represetative Philosophy of India and very source of Sanatan Dharm =Eternal Religion or Hindu Dharm .
In all the Religions of world including India some one has been founder of their Religions but Sanatan dharm has no founder whatsoever . likewise all the Philosophies have their founder even many in India all including Baudhism and Janism except Vedanta .
Really Vedanta is the spiritual crop of the Best Brains of India who devoted and sacrifised their lives in pursuit of REALITY / TRUTH but to great wonder they did not claim to be founders for three good reasons . 1 - this great effort was made by groups / group of best brains spread and unfolded over long span of time and experience , therefore no one could claim of it as his . 2 - they all were in agreement /consonance that this knowledge was a Vision of Reality when they were with It or in It . 3 - Because of their great / extreme Humility .
The theory of Vedanta says - there is only ONE ELEMENT called ATMA in Samskrit language and all the Creation is manifestation of this Atma . this Atma is Eternal all pervading and this whole Existence is nothing but ATMA itself . IT/ATMA is that exists in all and IT is CONSCIOUSNESS in all conscious and unconscious and pervade all that exists . IT is with good intent OMNISCIENCE , OMNIPOTENT AND OMNIPRESENT .( THAT we common eople personify for our understanding and call by various names as God .
This theory has not been negated so far by science and all theories similar to it are in agreement with it .