FiveM and ESX glossary

The terms that come up most when running a FiveM server, explained straight. If any of them sounds like gibberish, here it's made clear.

FiveM
A multiplayer modification platform for GTA V that lets you run your own servers (roleplay, racing, etc.). It is developed by Cfx.re and is not owned by Rockstar.
ESX
A roleplay framework for FiveM that provides the foundation of a server: players, money, jobs, inventory and items. It is one of the two most widely used frameworks, alongside QBCore.
ESX Legacy
The modern, actively maintained version of ESX. It changes some of the ways things are done compared to older versions, such as obtaining the shared object via exports['es_extended']:getSharedObject().
See the related guide
QBCore
The other major roleplay framework for FiveM. An alternative to ESX, with its own system of players, jobs and items. Many resources exist in both ESX and QBCore versions.
oxmysql
The most widely used MySQL/MariaDB database connector in FiveM. It lets resources save and read data (accounts, inventories, properties) asynchronously and safely.
ox_lib
A utility library that is very common in modern servers: menus, notifications, callbacks, caching and more. Many resources require it as a dependency.
MLO
Map Loader Object. A custom interior or map (police station, club, mechanic shop) added to the GTA V world to give your city new playable spaces.
fxmanifest.lua
The file that defines a FiveM resource: which scripts it loads on the client and server, its dependencies, the fx version and NUI files. Without it, the resource will not start.
server-authoritative
A security principle whereby important logic (granting money, items, permissions) is decided and validated on the server, never trusting the client. This is what prevents most cheating.
ensure
A server.cfg directive that starts a resource. Order matters: dependencies (es_extended, oxmysql) must come before the resources that use them.
See the related guide
getSharedObject
The ESX Legacy export for safely obtaining the shared ESX object: exports['es_extended']:getSharedObject(). Using it avoids the classic ESX nil error on startup.
See the related guide
NUI
New User Interface. FiveM's interface layer built on HTML/CSS/JS, which communicates with Lua through messages. It is what you use for menus, HUDs and panels inside the game.
recurso (resource)
The basic unit of FiveM: a folder with its fxmanifest.lua and its scripts. A server is a collection of resources started with ensure.
convar
A server configuration variable (for example sv_licenseKey or steam_webApiKey). Some are sensitive: a backdoor may try to leak them to a webhook.
backdoor
Hidden code in a resource that grants unauthorized access or control: a concealed admin, theft of your database or your keys. Common in leaks. Crxative-M's audit detects them.
resheller
A tool or piece of code that re-packages (re-shells) a resource to reinject a backdoor or bypass protections. One of the things a good security scanner looks for.
txAdmin
A web panel for managing and monitoring a FiveM server: starting it, viewing the console, managing resources, bans and backups. It ships with the server artifact.
Cfx.re
The organization behind FiveM and RedM. It manages server license keys and the infrastructure. Crxative-M is not affiliated with Cfx.re.
license key (sv_licenseKey)
The key that identifies your server to Cfx.re. It is sensitive: if leaked, others can impersonate your server. Never share it or leave it in code you upload to public sites.
webhook de Discord
A URL that lets you send messages to a Discord channel. Useful for logs, but also the typical way a backdoor leaks data from your server. Its presence in an unknown resource is a red flag.

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FiveM/ESX glossary — terms explained | Crxative-M