REALITY is but an illusion to some people but majority either wont care or not think about it so heres an answer to the question:

is reality or everything we know an illusion?

Now Reality is what we know as everything that is real is a part of it so let me explain scientist once thought or maybe they still do think that reality is just our minds thinking space and time is not real now everything from the past is but a stimulation or brainwashing of the so called "Common knowlege"

Because of the current state of humanity everything about the past is but what humans think technology isnt gunna prove anything because this is just them trying to unravel the truth.Reality isnt real it is but us thinking or dreaming about our own world if you are reading this this might be mine yours or somebodys world death is something that might wake us up or might bring us to another dream.The real reality will never be found unless somebody might solve if death will be our ESC.Button nothing we do is real if you want to go back in time you might or may not be able to do it.This world is up to the one that owns this dream."The Admin" of this stimulation or dream.