Players assume the role of the Postal Dude, a man who commits mass murder throughout the fictional town of Paradise, Arizona to cure what he believes to be a "hate plague" released by the United States Air Force.

Gameplay and interface are similar to first-person shooters of the time, but not on all counts: A man referred to simply as the "Postal Dude" has been evicted from his home.

He believes the United States Air Force is releasing an airborne agent upon his town of Paradise and that he is the only individual unaffected by the ensuing "hate plague".

He fights his way from his house to an Air Force Base through various locations, including a ghetto, train station, trailer park, truck stop, and an ostrich farm.

Suffering a mental breakdown amidst innocent laughter, he finds himself restrained in a mental asylum as hellish images cover the screen: A body bound to chains in a corridor, the protagonist in a straitjacket curled in the fetal position; a close-up of his face, covered in bindings; and the door to his cell numbered 593.

The lack of any mentions of military interference with the civilian population implies that the Postal Dude's murders were the result of his own paranoid delusions.

Amid distorted audio, the psychologist gives a final remark: "We may never know exactly what set him off, but rest assured we will have plenty of time to study him".

Due to the controversy surrounding the game's release, along with numerous American school shootings in the years following, the ending was changed in Postal Redux.

Replacing the elementary school vision is the player witnessing the burial of an unknown person in a decaying field, widely believed to be his own funeral.

Completion of the game on the hardest difficulty features the inclusion of an unknown male and female mourning over the grave as it descends.

Both outcomes prompt a similar mental breakdown and an identical asylum cutscene, though consisting of animated shots over the original release's still image artwork.

The character's "Postal Dude" moniker was coined by RWS CEO Vince Desi in an early interview about the game.

[14] Postal uses RSPiX, a cross-platform game engine developed internally at RSP[15] that was previously used for the company's child-friendly products, including Wishbone Activity Zone and Muppets Inside.

[29] Next Generation reviewed the PC version of the game, rating it four stars out of five, and stated that "Overall, Postal is a title that breaks absolutely no new ground, but its tongue-in-cheek shooting action comes together to form a well-above-average shooter that adds to the genre.

[22] GameSpot's Mark East gave the game a 6.6/10 score and commented: "The lack of longevity in the single-player mode and the simplistic multiplayer options make Postal a moderately fun ride, at best.