Groundspeed

The airplane’s speed over the ground, used for time and fuel planning.

As taught in Pilotage, Dead Reckoning and Time-Speed-Distance (Navigation and Sectional Charts) — a free lesson with cited FAA sources.

Speed of the aircraft over the ground, changed by head/tailwind components.

As taught in Wind, Groundspeed, Time and Distance (Cross-Country Flight Planning) — a free lesson with cited FAA sources.