Page "Quake (video game)" Paragraph 18

Before the release of the game or the demo of the game, id software released QTest on February 24, 1996.

It was described as a technology demo and was limited to three multiplayer maps.

There was no single player support and some of the gameplay and graphics were unfinished or different from their final versions.

QTest also gave gamers their first peek into the filesystem and modifiability of the Quake engine, and many entity mods ( that placed monsters in the otherwise empty multiplayer maps ) and custom player skins began appearing online before the full game was even released.