What exactly is a "g"? I've heard it used to describe the force of gravity, and the acceleration due to gravity. It surely can't be both. Sitting here in my chair, I am not accelerating. Am I experiencing 1g (force) or 0g (acceleration)? What about a spinning space station, far enough away that Earth's gravity is negligible, but spinning fast enough to simulate gravity (9.8 m/s^2 at the outer wall). Are the astronauts, standing on this wall, experiencing 1g (acceleration) or 0g (force)?