What is gravity?

I am not asking why it occurs, but what it is. Everything understood is something.

Something would entail the existence of a property, whether or not tangible.

We know photons exist, but we know they are subatomic particles.

Speaking on states and matter, is gravity matter? Does it have states? Is it solid, liquid, gas, plasma? Is it atomic, subatomic, etc.?

Natural phenomenom doesn't tell me absolutely anything about what gravity is.

So I ask again in pure simplicity ... what is gravity?

Is gravity magnetism? As such it would be a force. But I've been told that's incorrect.

Also, Eintein's "theory" doesn't answer any of these questions:

1.What causes gravity?

2.What is gravity?

3.Is gravity a force?

4.Can gravity be controlled?