In early shooters, it was considered too memory intensive for games to write bullet impacts into walls. Early iterations of Doom show that there was an attempt to show bullet impacts, but these were later scrapped. Players would be able to fire at walls and perhaps see where the bullet impacted, as in Doom, but it would take later developments in computers and software in order to efficiently show player effect on the environment.
One way many games began to introduce this concept was to make the bullet impact its own sprite, which would be placed in front of the wall hit. This would sometimes break the illusion when the impact would be near the edge of the wall, and the sprite would hang over the edge, half-floating in midair. Another tactic would be to change the wall texture itself, but writing the wall texture over again rarely produced convincing results, and took up significant space.
These techniques were refined and improved as 3-D technology advanced, and now games will often have very complex damage states for surfaces that older games could never have matched. This includes warping of surfaces, and even detailed destruction of surfaces.