Space in its simplest explanation is the combination of distance and time ruled by energy. You could think of it as liquid, in fact the math to describe the properties of liquids oddly applies to space, but unlike a liquid it compresses and stretches.
Newton says the apple, and imperceptibly the Earth, simply traveled to meet one another. In relativity, an apple falls because its internal clock is going faster than the planet’s clock (why? because it’s in less dense space. Density is determined by mass which then causes the curvature of space..time... spacetime), so the apple is simultaneously falling to Earth, and through time.
Making it denser at the center and less dense on the edges, creating an omnidirectional curvature around a body. The greater the mass, the greater the curvature. Note: size is not related to this concept.
Near a mass, space’s density increases and it gets denser the closer you get to the center. Going outward it thins back toward the baseline, and it reaches the baseline only at infinite distance. Which means that every object in space is influenced by one another. Though the effects could never be measured.
I work in IT. Astronomy and physics have been the passion alongside it for as long as I can remember.
I built this because the rubber sheet does not explain gravity properly. It shows a ball denting a surface, which is a picture of something falling into a hole. It is not a picture of what mass does to space.
Relativity is also hard to grasp if you do not understand that you need a point of reference. That was my own sticking point while making this. Things kept getting described as relative without the thing they were relative to ever being named. Once you fix the reference, it stops being slippery.
That is why the stars are here. They give you frames of reference for navigation, and they do exactly the same job for time dilation.