I often hear people talking about using the GECK for Fallout. I have never come across this item in any of the games. What is the GECK and what does it do?
GECK is an acronym which stands for "Garden Of Eden Creation Kit". For fans of the series, you will recognize this terraforming device that can save the wasteland from the games. Outside of the Fallout series, the GECK is a tool created by the Fallout developer for the creation of mods.
The GECK mod creation kit is the Fallout equivalent of the Elder Scrolls Construction Kit. The tool offers a robust scripting language and other tools that allow modders to create landscapes, dialog and various other features that can be used for modding.
The GECK was used for Fallout 3 and Fallout: New Vegas. There is currently a modding tool being developed by Bethesda for Fallout 4, but it is currently unknown of this tool will also be called the GECK. The Fallout 4 edition of the tool my differ from previous versions as Fallout 4 is the first Fallout game to allow mods on the console version of the game.
More information including download links to the Fallout GECK tool can be found on the official Garden Of Eden Creation Kit(GECK) website.