If you've landed here, you've probably heard of Garry's Mod — or you're running a server and want to understand the bigger picture.
This guide covers the basics: what a GMod server actually is, how multiplayer works, the different gamemodes, and why the thing players see while they connect (the loading screen) deserves more attention than most server owners give it.
What is Garry's Mod?
Garry's Mod (GMod for short) is a physics sandbox game released in 2006 by Facepunch Studios. There are no built-in objectives. Instead, it gives you tools to spawn objects, weld them together, ragdoll NPCs, and build contraptions using the Source engine (the same engine behind Half-Life 2, Counter-Strike: Source, and Team Fortress 2). Think of it as a virtual toy box where the only limit is your creativity — and your computer's framerate.
What makes GMod special is its modding community. Over the years, players have built entire game modes inside the sandbox: roleplay servers, murder mystery games, driving simulators, and more. These are made possible by dedicated servers that host the experience for other players to join.
What is a GMod server?
A Garry's Mod server is a dedicated instance of the game running on a machine (a PC, a VPS, or a rented game server) that other players connect to. Unlike single-player sandbox mode, a server lets multiple people share the same world. The server runs the gamemode, enforces the rules, and keeps everyone in sync.
Servers are what make GMod a multiplayer experience. Without them, you'd be building alone in your own world. With a server, you can build with friends, roleplay with strangers, or compete in minigames — all in real time.
Who runs GMod servers — and why?
Anyone can run a GMod server. You can host one on your own computer for friends (using the "Create Server" button in the main menu), or rent a dedicated server from a hosting company for a public community. Here are the most common reasons people run servers:
- Building a community: the biggest reason. A DarkRP or MilitaryRP server with regulars, staff, and events becomes a true online community. People come back for the people as much as the gameplay.
- Playing with friends: a private server where you and your friends can build contraptions, test addons, or mess around without strangers.
- Trying out gamemodes: some gamemodes have very few active public servers. Running your own lets you play exactly what you want.
- Learning server administration: running a GMod server teaches you Linux, networking, coding (Lua), and community management. Many sysadmins started with a game server.
The main GMod gamemodes
The default GMod menu offers Sandbox, but the real variety comes from community-made gamemodes. Here are the most popular ones you'll encounter:
- Sandbox — the original. Build whatever you want with unlimited props, tools, and welding. Creative, chaotic, and completely freeform.
- DarkRP — a roleplay gamemode set in a city. Players take jobs (police, criminal, medic, mayor), earn money, buy properties, and live out urban stories. The most popular GMod gamemode by a wide margin.
- TTT (Trouble in Terrorist Town) — a social deduction game where traitors hide among innocent players. Figure out who's killing before you're next.
- MilitaryRP — a structured roleplay gamemode with regiments, ranks, and chain of command. Players simulate military operations with discipline and hierarchy.
- Prop Hunt — one team disguises as props (barrels, chairs, toilets) while the other team hunts them down. Simple, silly, and endlessly replayable.
- Deathrun — an obstacle course gamemode where one player triggers traps and everyone else tries to reach the finish line. Pure chaos.
Each gamemode has its own community, rules, and expectations. If you run a server, your gamemode shapes everything: your addons, your rules, your Discord culture, and your loading screen. We've written a dedicated guide on tailoring your loading screen to each gamemode.
What happens when a player joins your server
When a player clicks "Join" on your server in the GMod browser menu, a specific sequence of events kicks off:
- The client contacts the server and starts negotiating the connection.
- The server sends a list of required files: maps, models, sounds, materials, and Workshop addons the player doesn't already have.
- The client starts downloading everything it needs. This is where the loading screen appears.
- Once the download finishes, the client loads the Lua code for the gamemode and all addons.
- The player spawns in the world, ready to play.
Step 3 is where most of the waiting happens. First-time joins can take anywhere from 30 seconds to 10 minutes, depending on how much content your server uses. That screen they stare at during those minutes? That's your loading screen. And it's the topic of everything else on this blog.
Why the loading screen matters (even for beginners)
If you're new to running a server, the loading screen probably sounds like a cosmetic afterthought. It's not. Here's why:
- It's the first thing players see. Before they spawn, before they type a single command, they're looking at your screen. A blank or default screen says "this server is empty and abandoned."
- It fills the wait with purpose. A progress bar that actually moves, a file name scrolling by — these reassure players that the connection is working. Without them, people assume it crashed and leave.
- It's a captive audience for your rules. Players have nothing to do but look at the screen. That's the perfect moment to show your Discord, your top rules, and your staff. They'll actually read them.
- It sets the tone. Music, colors, branding — a well-made screen tells players what kind of server they're joining before they even spawn.
Our article on loading screens and player retention dives deeper into the data behind this.
What you need to run a GMod server
- A computer or VPS — can be your own PC for small private servers, or a rented server from a game hosting company. Hosts like GTXGaming, Fragnet, or OVH are popular choices.
- GMod server files — installable via SteamCMD on Linux or Windows. The server itself is free once you own GMod on Steam.
- A configuration file — server.cfg, where you set the hostname, password, RCON, and
sv_loadingurl(the loading screen URL). - Addons and a gamemode — Workshop collections for content, and a gamemode like DarkRP or TTT installed on the server.
- A loading screen URL — either self-hosted or generated with a service like Lumescreen. This is what players see while they download your content. Our step-by-step installation guide shows you how to wire it up.
Where to go from here
Now that you know what a GMod server is and why the loading screen matters, here are the next articles to read depending on where you are in your journey:
- Just starting out? Create your first loading screen — the complete walkthrough.
- Already have a URL? Install it on your server — get sv_loadingurl working in 5 minutes.
- Want to make it look good? Customize your screen — music, rules, staff, and live server info.
- Players not staying? Learn about retention — how the loading screen keeps people on your server.
- Need a quick fix? Troubleshoot common issues — your screen isn't showing? Start here.
Or, if you just want a working loading screen without any of the setup, Lumescreen gives you a hosted URL with themes, music, analytics, and live server data. It's free to start, and the only config you need is one line in server.cfg.