First off, there are no proven theories of what reality actually is, or proof that what we perceive as reality is anything other than just a subjective mental dreamlike construct of awareness generated by our omnipresent consciousness.
Our senses are just a concept of this inward mentalism of self awareness, which generates logical thought through our need to measure and classify reality objectively.
Some believe we are all connected by an ultra fine universal two dimensional elastic medium that permeates all things. This quantum field is the alleged birthplace of time, electro-magnetism, gravity, microwaves, light, heat, sound and matter.
All of these conditions are just varied rates of vibration/oscillation in resonant sympathy within the quantum forces that interact with our consciousness directly.
Our bodies are comprised of tiny "wave particles" of boundary layers born from these mediums moving in a constant state of multi-direction of motion to and from the rotational time domain we perceive as reality.
Since there is no reference frame from which any state crosses from one medium to another the direction of time is also an illusion.

So in essence, we are not truly "real". We can only exist as living awareness moving in a constant "now".
Solid matter is an only an illusion to living consciousness.
It is simply a collection of varied vibrations moving so fast or slow that it appears to be solid.

Some believe at one point, the collective consciousness of our species fractured from the oneness of omnipotent universal thought and became unique or singular, like a shattered hologram that still retains the sum of the whole despite the separate pieces.
We call this Phenomenon Freewill.
We are dividual but still retain the desire to be whole.
Since we are experiencing consciousness from a singularity, we are only capable of creating a universe around us in the form of subjective collective experience.
In other words for "I" to exist you must exist also. As no two points can occupy the same space and time we see this seperation as shared collectice conscious substance, our observations of reality are based from learned behaviors we have accepted for truth.
Most of us agree to limit our existence from birth based on the face value of others perceptive experience and as a result, our subjective reality perpetuates itself in a feedback of repetitive patterns of beliefs, much like a needle stuck on a record.