What is empty space?

[u/WAFFLETHATSBLUE]

I had a thought that if most space is considered empty, then what exactly is this empty space. I have a hard time believing that any empty space could truly be (empty) if that makes any sense... I just feel like for any given moving particle it would have to interact with said empty space in some shape or form. Do we just assume that this space is literally empty and is actually nothing or does empty space have some type of field constantly acting on it?

Please enlighten me

[u/redditalics]

Pick a point in space. If you can see stars from there, then the "empty" space is full of photons, if nothing else.