Glossary
Every term the docs, UI, and API use consistently, with foundational concepts getting a paragraph, lookups a single sentence, and almost every entry linking out to a dedicated page for full detail.
Admin: highest user role. Full scope set, including user management and task execution (see Users & Roles).
API token: see Client API Token.
Asset: user-uploaded content attached to a ROM, such as save files, emulator states, and screenshots. Assets live under /romm/assets (separate from the library) and are owned per-user. Saves and states can sync to registered devices, and are not the same as a Resource (see Saves & States).
Autologin: OIDC feature that bypasses the login page and redirects straight to the IdP. Set via OIDC_AUTOLOGIN=true.
Basic auth: HTTP auth with username+password in a header. Supported for API calls.
BIOS: see Firmware.
Client API Token: long-lived bearer token scoped to a user. Used by companion apps (Argosy, Grout, Playnite, custom scripts) to authenticate. Each user gets up to 25 active tokens, and tokens can be paired to devices via a short code (see Client API Tokens).
Collection: a named grouping of ROMs (see Collections).
Device: a registered endpoint that syncs with RomM, such as a handheld running Grout, an Android phone running Argosy, or a SteamDeck running DeckRommSync. Devices pull saves and states, and some push them back after a session (see Device Sync Protocol).
EmulatorJS: the bundled in-browser retro emulator. Handles NES, SNES, N64, PSX, Saturn, and 20+ more cores (see In-Browser Play → EmulatorJS).
Facet: one axis a recommendation is explained by, such as a shared franchise, genre, theme or developer. A facet counts for as much as it is rare in your own library.
Feed: a URL endpoint that exposes a filtered library view in a third-party tool's expected format (see Feed Clients).
Firmware: BIOS or system firmware required for certain emulators (PS1, GBA, Saturn, etc.). Lives wherever the filesystem.structure.firmware template points, bios/{platform} by default. Uploaded via the UI and managed by admins and users with the firmware.write scope (see Firmware Management).
Full image: the default container variant, bundling all four browser runtimes (EmulatorJS, Ruffle, js-dos, FAKE-08). rommapp/romm:X.Y.Z (see Image Variants).
Game Data tab: the ROM detail page tab for saves, states, and screenshots. User-specific.
gamelist.xml: ES-DE/Batocera-compatible metadata format. Importable as a metadata source and exportable.
Invite link: single-use URL that lets a new user register with a pre-assigned role (see Invitations & Registration).
Jukebox: the library-wide soundtrack player, reading the audio files in each game's soundtrack/ folder (see Jukebox).
Kekatsu: Nintendo DS multiboot loader that reads RomM's feed (see Kekatsu).
Kiosk mode: server-side setting (KIOSK_MODE=true) that turns every read endpoint into unauthenticated access. Anonymous visitors can browse but nobody can write, which fits public demos and wall displays (see Authentication → Kiosk mode).
Library: your ROM files on disk. Mounted at /romm/library inside the container, and laid out according to your structure templates. The catalogue is built from what's found there (see Folder Structure).
Memory card: on PS2 and GameCube, the emulator's whole card kept in your RomM library rather than on the streaming container, with versions and sharing (see Emulator Streaming → Memory cards).
Metadata provider: external source of game data, queried during a scan, with results merged. Configured via env vars + priority in config.yml (see Metadata Providers).
Netplay: EmulatorJS's multiplayer mode. Two or more players share a session across the internet. Open rooms are tracked and brokered via WebSocket. Needs STUN/TURN (ICE servers) configured in config.yml for reliable NAT traversal (see Netplay).
OIDC: OpenID Connect. Supported SSO protocol for external auth (see OIDC Setup).
OpenTelemetry (OTEL): opt-in traces/metrics/logs export. OTEL_ENABLED=true (see Observability).
Permission group: a named template of capabilities (a grant matrix over entity types × read/write/delete) assigned to a User. One group is the server-wide default for new users. Admins bypass groups entirely (see Users & Roles).
Personal tab: the ROM detail page tab for per-user data (rating, status, notes, playtime).
Physical game: a library entry for a copy you own on cartridge or disc, with no file on disk. Added by name or by barcode, and excluded from anything that needs a real file (see Physical Games).
Platform: a gaming system: SNES, PlayStation, Game Boy Advance, DOS, etc. ~400 platforms ship supported. Each has a slug (snes, psx, gba) that doubles as the folder name expected in your library, alongside the folder name aliases other frontends use. Override the folder-name → slug mapping via config.yml (see Supported Platforms).
Play session: a timestamped record of someone playing a ROM (start, end, duration, device). Used by the stats, the Continue Playing ribbon, and per-ROM playtime totals. Ingested automatically when playing in-browser, and companion apps push them via API.
PWA: Progressive Web App. Install RomM to your phone or desktop home screen via your browser's add-to-home-screen flow. Requires HTTPS.
Resource: provider-fetched metadata image (cover art, screenshot, manual) stored under /romm/resources. Machine-managed and rebuildable from a rescan. Not the same as an Asset (/romm/assets), which is user-owned and not recoverable from the library.
ROM: a single game entry. One filesystem file, one folder of files (multi-disc, patched, with DLC), or a manual DB entry. Each ROM belongs to exactly one platform. ROMs get metadata (cover, description, ratings, related games), user data (per-user rating, notes, playtime), and optional assets (saves, states, screenshots, firmware).
Role: an account's top-level type. Two roles: User (access governed by a permission group) and Admin (full access, bypasses groups). See Users & Roles.
Ruffle: the bundled in-browser Flash/Shockwave emulator (see In-Browser Play → Ruffle).
Scan: the process of walking the library, hashing files, calling metadata providers, and updating the DB. Scans run in six modes (New Platforms, Quick, Unmatched, Update, Hashes, Complete) and can be triggered manually, on a cron, or by the filesystem watcher (see Scanning & Watcher).
Scope: a coarse OAuth permission derived from a user's effective permission-group grants. Client API Tokens and OIDC sessions carry a subset of the user's scopes (see Users & Roles → API tokens).
Session (streaming): one claim on a streaming container. A container drives one display, so it holds one session at a time, bound to the user who claimed it (see Emulator Streaming).
Setup Wizard: first-run flow that creates the admin user. Shown before any user exists.
Smart Collection: rule-based auto-populating collection (see Smart Collections).
socket.io: the WebSocket protocol. Two endpoints: /ws and /netplay (see WebSockets).
Task: a unit of background work (scan, metadata sync, cleanup, device sync). Runs through RQ. Can be scheduled (cron), watcher-triggered, or manual (see Scheduled Tasks).
Tinfoil: Nintendo Switch homebrew that installs from RomM's feed (see Tinfoil).
Title id: the platform-native identifier read out of a ROM's own binary during a scan, on the platforms that have one. Identifies a game where RomM doesn't hash, and says where the game writes its saves (see Scanning & Watcher).
User: an account. Its role is either User (access from a permission group plus per-user overrides) or Admin (full access). Can be created by the Setup Wizard, an admin, an invite link, or OIDC auto-provisioning (see Users & Roles).
Valkey: open-source Redis fork, drop-in compatible (see Redis or Valkey).
Virtual Collection: auto-generated collection by genre/developer/year/tag. Read-only (see Virtual Collections).
Walkthrough: a guide document attached to a game, stored in its walkthrough/ folder beside its manual, uploaded or imported from a GameFAQs URL, with per-user reading progress (see Walkthroughs).
Watcher: filesystem watcher that triggers scans on file events. ENABLE_RESCAN_ON_FILESYSTEM_CHANGE=true (see Scanning & Watcher).
webstation: the single container every streamed emulator runs in, serving as many platforms as you point at it (see Emulator Streaming).
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