The `.doom` file is a feature for easy loading of doom files with mods, it is based on the work done by [AmberELEC .doom](https://amberelec.org/systems/doom.html) and others with additional improvements made by RetroDECK.
In this example we are making two folders under the `/roms/doom/` folder, with the goal of just using .doom files as the primary way to play doom games.
In the `iwads` folder you can put one or all of the official files game wads made by ID Software/Bethesda their addons and/or freedom so they are not mixed up with the mods.
In the `mods` folder you can put all the extracted mod files. By putting them all into one folder and no subfolders you easily make sure you have no duplicate files as they would be in conflict.
In the root of the `roms/doom/` folder put all the `.doom` files you will create or download.
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Result
When you launch the ES-DE interface from RetroDECK and navigate to DOOM category, all the `.doom` files will be listed first as your primary game list while the rest of the files are in their respective subfolder.
## What is the .doom file and how do you create it?
The `.doom` file is just an empty text file that is populated with the exact filenames of the files you want to load and in what order from top to bottom.
You should name the `.doom` file so you understand what it is, for example: `Project Brutality.doom`.
Each line represent one file, as long as the mods are compatible with each other you can add how lines as you want.
The parser does not allow spaces currently in the mod files so if your modfile is called for example `PB Staging 9f2561c.pk3` rename it to `PB_Staging_9f2561c.pk3` with `_` instead of spaces.
### I come from one of the ELEC's what does RetroDECK do different with the .doom file, can I migrate?
RetroDECK have written a new parser from the ground up. You no longer need to write the path in the .doom files. RetroDECK scans all folders and subfolders of `/roms/doom/` only put the name of the mod file. If you are migrating to RetroDECK all you need to do is remove the path in your .doom files.