Plugin file used by The Elder Scrolls (TES) first-person RPGs such as Oblivion and Skyrim; similar to an .ESM file but is used specifically for adding plugin features, such as new graphics, weapons, and world content; used for creating custom game alterations.

In order to apply custom game modifications, ESP files interact with ESM (Master) files and override default behaviors and data. While ESP files can be used for plugins, often users will create mods of ESM files and distribute them for custom game alterations without using ESP files.

Plugin file used by the Fallout 3 and Fallout: New Vegas futuristic post-nuclear war role-playing games; contains a plugin that modifies game content; can include game objects, dialogue, gameplay settings, AI settings, world properties, and other content.

ESP files can be used for modifying existing game data or for adding new game data. They can be edited using G.E.C.K. (the Garden of Eden Creation Kit), which is made available by Bethesda Softworks, the developers of the Fallout series. ESP plugin files are complementary to .ESM master files and will not load without a corresponding ESM file. Additionally, the settings in ESP files override those in ESM files, since the ESP game data is always loaded after the ESM data. Therefore, you can use ESP files to override the default game properties with custom properties.