>>382203S.T.A.L.K.E.R. is a coded acronym, literally: Scavenger, Trespasser, Adventurer, Loner, Killer, Explorer, and Robber.
Think a modern, gritty Indiana Jones in a radioactive, actively hostile wasteland that is bit Innawoods and Borderlands at the same time (sort of).
As for this thread, it pertains mostly to Urban/Rural Exploration, mainly of abandoned structures, as this is a prominent activity in the actual S.T.A.L.K.E.R. game.
Quite fun, really. You might consider trying it sometime. :)