Visual flight rules (VFR) is a set of regulations governing aircraft operations. VFR permits flying and navigating by visual reference outside the aircraft.
Visual flight rules (VFR) is a set of regulations governing aircraft operations. VFR regulations allow a pilot to fly and navigate by looking outside the aircraft and is permitted only when weather conditions are good enough to give the pilot a continuous view of the ground.
Some countries may allow VFR over the top, where a VFR flight temporarily loses visual contact with the ground as it flies over - but not into - cloud.
VFR is usually contrasted with IFR (instrument-flight-rules); all flights operate under either VFR or IFR. VFR should not be confused with vmc (visual meteorological conditions), which are weather conditions in which VFR is allowed.