Widescreen rendering for using all the available horizontal space of screens with aspect ratios up to 24:9.
Enhanced 640x400 display resolution, with the original 320x200 resolution still available in the "High Resolution Rendering: Off" mode.
So Doom inherits all the core features of its parent Crispy Doom:
Extra options for some Crispy settings (like weapon bobbing).
Possibility to interpolate camera movement only ('Camera movement' setting of 'Uncapped framerate' menu item), so that monsters don't 'slide'.
In-game control of pixel aspect ratio correction (not having to edit the so-doom.cfg file manually).
Option for INTERCEPTS overflow evasion in singleplayer, shadowed and disabled in netgames.
Hot-swapping of Crispy Doom's Flipped Levels and Flipped Weapons features.
It is forked off of Crispy Doom to take advantage of its free and open-source code base, portability, accuracy and compatibility with Vanilla Doom. So Doom is a source port that aims to provide a faithful Doom gaming experience while also featuring some user-requested improvements and enhancements. So Doom is a friendly fork of Crispy Doom that removes the static limits of the Doom engine, including a singleplayer-only optional removal of INTERCEPTS limit. Its name is a tribute to Sodom, German thrash metal band. So Doom is a limit-removing enhanced-resolution Doom source port based on Crispy Doom.