In Star Trek, what technology reduces the effects of sudden acceleration aboard a starship?

In Star Trek, an inertial damper reduces the effects of sudden acceleration aboard a starship.

Starships routinely accelerate to extraordinary speeds, especially when entering or leaving warp. Without fictional protection, the crew and equipment would experience lethal forces. Inertial dampers are therefore presented as systems that counteract or absorb those effects, allowing people to remain standing while a vessel performs maneuvers that real spacecraft could not safely perform.

The system is usually discussed alongside structural integrity fields. The inertial damper protects occupants and movable contents from acceleration, while the structural integrity field helps keep the ship itself from being torn apart by stresses. Star Trek stories sometimes show either system failing during battles or emergencies.

This technology is different from artificial gravity. Artificial gravity keeps decks usable and objects pulled toward the floor, but it does not by itself cancel acceleration forces. The two systems operate as separate pieces of a starship’s fictional environmental and flight technology.