Used for example to write GTA SAMP modes. I remember writing them in Pawno IDE. The scripts would get large as I'd export positions of many objects and paste them into the scripts to spawn in game. Makes for an okey "how I started programming" story.

See also Sourcepawn[0], popular in the sourcemod engine community for custom server plugins and game modes.

[0] https://github.com/alliedmodders/sourcepawn

A slightly modified version of this was used as the gameplay scripting language in Pokémon games from gens 6 to 8:

https://github.com/SciresM/gf-pawncc