What is "vtvl"

Vertical takeoff, vertical landing (VTVL) is a form of takeoff and landing for rockets. Multiple VTVL craft have flown. , VTVL is under intense development as a technology for reusable rockets, with two companies, Blue Origin and SpaceX, both having demonstrated recovery of launch vehicles, with Blue Origin's New Shepard booster rocket making the first successful vertical landing following a test flight that reached outer space, and SpaceX's Falcon 9 Flight 20 marking the first landing of a commercial orbital booster.

VTVL rockets are not to be confused with aircraft which take off and land vertically which use the air for support and propulsion, such as helicopters and jump jets which are VTOL aircraft.