So I heard someone (Neil) describe 4 types of orbits, circular, elliptical, parabolic, and hyperbolic.
I'd argue in reality circular and parabolic are boundary cases that never exist in real life. So in reality all orbits are elliptical (though may be arbitrarily similar to circular) and hyperbolic (which also may be arbitrarily close to being parabolic).
@kilroy_was_here It is useful for exactly what I said, as a boundary condition. It is worth understanding them but its also important to understand they arent observed in the real world and they exist only as a boundary between 2 classes.
@freemo
I'd imagine it's one of those things where it's useful in math and simulations even if it's an edge case in reality.