Glossary
Every term you'll run into on project pages and in the forum, in one sentence each.
| Term | Meaning |
|---|---|
| Passthrough mod | Two real games run at once and share data, so one plays inside the other. |
| Host | The game you see and play in. |
| Guest | The game brought into the host, usually running hidden. |
| Hidden / headless | Running without showing a window, or without drawing anything at all. |
| Shared memory | A block of memory both games can read and write: the fastest way for two programs to talk. |
| IPC | Inter-process communication: any way two programs talk (shared memory, sockets, pipes). |
| Compositing | Layering one game's picture into another's. |
| Depth (buffer) | How far away each pixel is. Lets one game's objects hide correctly behind the other's walls. |
| Collision | The invisible shapes a game uses for physics: what you can walk on and bump into. |
| Proxy | An invisible stand-in for a character from the other game, so this game's AI can "see" it. |
| Mod loader | A tool that lets a game load extra code (SKSE, Fabric, BepInEx…). |
| Script extender | Bethesda-game mod loaders: SKSE (Skyrim), F4SE (Fallout 4), xNVSE (New Vegas). |
| DLL injection | Loading your own code into a running game. How many loaders work, and why antivirus gets nervous. |
| ASI plugin | A DLL that a game's ASI loader picks up (common in GTA modding). |
| Address Library | A Skyrim/Fallout mod that keeps plugins working across game versions. |
| Rust rewrite | A game's engine written again from scratch (often in Rust with Bevy) that loads your own game files. |
| Bevy | A free, open-source game engine written in Rust. |
| Decompilation (decomp) | Turning a game's machine code back into readable source code. |
| Matching decomp | A decomp that compiles back into byte-for-byte the original game. |
| Static recompilation (recomp) | Translating console code into native PC code ahead of time, instead of emulating it. |
| Bring your own files | You supply the game data from your own copy; the project never includes it. |
| Clean-room | Rebuilt without copying the original's code or assets. |
| Anti-cheat | Software in online games that detects modified clients. Modding those can get you banned. |
| Proton | Valve's compatibility layer for running Windows games on Linux and Steam Deck. |
| Fork | A copy of someone's repository that you can change. Most passthrough ports started as forks. |
| Release | A packaged version of a project, usually with a downloadable zip. |
| Verified (on this site) | A moderator checked the listing points to the genuine, official project. |