Is gravity a force, or a bend in space and time?

Both descriptions work: gravity is a force in Newton's model, and a change in the shape of space and time in Einstein's. Which description you need depends on what you are trying to explain. They are ways to describe the same world, with different ranges of use.

The question often starts with a small puzzle. A dropped cup falls, but the Moon stays up. Astronauts float, yet their spacecraft stays near Earth. These scenes can seem to call for different rules. Looking at the motion helps connect them.

An orbiting planet is still falling toward the Sun. Its sideways motion carries it onward while gravity bends its path. A spacecraft in orbit falls too. The people and loose objects inside fall with it, so they float relative to one another. Floating does not mean that Earth's gravity has switched off.

The Moon gives us another useful clue. It turns once on its axis during each trip around Earth. That matched motion keeps much the same side facing us. Earlier in its history, tides changed its spin. This is called tidal locking; it does not mean the Moon stands still.

You do not have to choose between an apple and a curved universe. The force picture helps with everyday motion. The deeper picture connects gravity to spacetime: the combined description of where and when events happen. Tests with satellites and waves from distant events let scientists check that picture against measurements.

There is still a frontier. Physicists do not yet have a tested, complete account joining gravity with the quantum rules used for tiny particles. That gap matters. It does not erase the parts of gravity that we can measure and use.