PPE file extension is used for files related with S.T.A.L.K.E.R. computer game series. S.T.A.L.K.E.R. is a first-person shooter (FPS) with narrative elements developed by GSC Game World for Windows platform.

PPE is a binary file format used for storing visual effects used in the game, such as night vision filters, bloom effects, radiation effects, drunkenness, etc. PPE files thus store post-process effectors data.