Ii it 2 names for one thing.
A false ceiling are squares on metal borders that hang from the real ceiling which is permanent. False ceilings are used to cover up messy ceilings or wiring running across ceilings.
A normal' ceiling is usually seamless drywall or plaster. A false ceiling is a metal grid system that will hold 2'x2' or 2'x4' tiles that can be raised to access wiring or plumbing.