Besides delivering essential supplies like propellant and water, what critical orbital function did the ATV perform?

Answer

Re-boosting the station’s altitude

Crucially, the ATV was utilized for re-boosting the station’s altitude, using its propulsion system to counteract the constant loss of altitude due to atmospheric drag.

Besides delivering essential supplies like propellant and water, what critical orbital function did the ATV perform?
SpacecontributionISSSpace StationESA