Roblox networking tutorial content usually starts with one specific, annoying realization: you just built an awesome feature, but it only works for you. You click a button, your character turns blue, but to every other player in the game, you're still standing there looking completely normal. It's the ultimate "it works on my machine" moment, and in the world of game dev, we call this a replication issue. Understanding how to bridge the gap between what one player sees and what the server knows is the single biggest hurdle for any new scripter.
If you've ever felt like pulling your hair out because your scripts aren't "syncing," don't worry. Networking is notoriously one of the hardest things to wrap your head around when you're first starting out. But once you get the hang of it, you'll realize that Roblox actually gives us some pretty slick tools to handle it.
The Two Worlds: Client vs. Server
Before we dive into the code, we have to talk about the "Two Worlds" problem. In any roblox networking tutorial, the most important concept is the distinction between the Client and the Server.
Think of the Server as the ultimate truth. It's a computer sitting in a data center somewhere that runs the "official" version of your game. It keeps track of everyone's scores, where the parts are, and who is winning.
The Client, on the other hand, is just the player's computer or phone. The client is basically a window looking into the server's world. When you move your mouse or press a key, that's happening on your client. The tricky part is that, for security reasons, the client isn't allowed to tell the server what to do directly. If players could just tell the server "Hey, I have a billion gold now," hackers would ruin every game on the platform within five minutes.
This boundary is called FilteringEnabled. It's the gatekeeper that prevents "Client-side" changes from automatically showing up for everyone else. To get past it, we need to use something called Remotes.
RemoteEvents: The Messaging System
RemoteEvents are the bread and butter of Roblox networking. If you want to tell the server that a player just clicked a "Buy" button or swung a sword, you use a RemoteEvent.
Think of a RemoteEvent like a one-way radio message. You're on the client side, you pick up the radio, and you say, "Hey Server, I just clicked the 'Fire' button." The server listens, checks if you actually have a gun equipped (because we don't trust the client!), and then does the work of making the bullet appear for everyone.
How to use them
Usually, you'll put your RemoteEvents in ReplicatedStorage. This is a special folder that both the client and the server can see.
- Client Side (LocalScript): You use
:FireServer(). - Server Side (Script): You use
.OnServerEvent:Connect().
It sounds simple, but here's a pro tip: always pass as little data as possible. You don't need to tell the server "The player clicked the button and they have 50 health and their name is Bob." The server already knows who sent the message! When you use FireServer, the player object is automatically sent as the first argument to the server script.
RemoteFunctions: The Two-Way Street
Sometimes, a one-way message isn't enough. You might need to ask the server a question and wait for an answer. For instance, "Hey Server, do I have enough money to buy this legendary sword?"
This is where RemoteFunctions come in. Instead of just firing a message and moving on, the client "invokes" the function and pauses until the server sends a response back.
However, a word of caution for anyone following this roblox networking tutorial: be careful with RemoteFunctions. If the server script has a bug or takes too long to respond, the player's game might freeze or hang while it waits for an answer that's never coming. Most experienced devs try to use RemoteEvents whenever possible and only break out RemoteFunctions when they absolutely need a return value.
Why You Should Never Trust the Client
We touched on this earlier, but it's worth repeating because it's the number one cause of games getting ruined by exploiters. In your networking logic, the server must always be the judge.
Let's say you have a shop. If your LocalScript (the client) calculates the price and tells the server "I'm buying this for 0 gold," and your server script just says "Okay, sure!", you've got a problem. A hacker can easily go into their console and change that 500 gold price tag to -99999.
Instead, your client should just say, "I want to buy Item X." The server should then look up the price of Item X in its own internal database, check the player's current balance, and then—only if they have enough money—subtract the gold and give the item. The client is just a suggestion; the server is the law.
Dealing with Lag and Latency
One thing you'll notice quickly is that the internet isn't instant. If a player in Australia is playing on a US server, there's going to be a delay (ping) between them clicking a button and the server receiving the message.
This is why "Client-Side Prediction" is a thing. If you've ever played a game where your character moves instantly when you press 'W', but other players seem to jitter slightly, that's networking at work. Roblox handles basic character movement for you, but for custom systems (like a fireball projectile), you might want to show the effect on the shooter's screen immediately so it feels responsive, while the server handles the actual damage a split-second later.
It's a balancing act. If you make everything wait for the server, the game feels sluggish. If you make everything happen on the client, the game feels "fake" and desynced.
A Simple Practical Example
Let's look at a classic scenario: a "Click for Points" game.
If you just put a script inside a button that adds +1 to a Leaderstat, it might work in Studio, but in a real game, it might not replicate properly depending on how you've set it up. Here is the right way to do it using our networking knowledge:
- Create a RemoteEvent in ReplicatedStorage and name it
AddPointEvent. - Create a LocalScript inside your Button UI. When the button is clicked, it calls
game.ReplicatedStorage.AddPointEvent:FireServer(). - Create a regular Script in ServerScriptService. This script listens for the event:
lua game.ReplicatedStorage.AddPointEvent.OnServerEvent:Connect(function(player) -- The 'player' variable is automatically given to us! player.leaderstats.Points.Value += 1 end)This is the "Gold Standard" for basic networking. The client requests an action, and the server carries it out.
Keep it Organized
As your game grows, you're going to end up with dozens, maybe hundreds, of RemoteEvents. If you just throw them all into the root of ReplicatedStorage, it's going to become a nightmare to manage.
Most pro scripters create folders. Have a "CombatEvents" folder, a "MenuEvents" folder, and so on. Some people even use "Bridge" modules to handle all networking in one place, which keeps the code clean and prevents you from having to type game.ReplicatedStorage a thousand times.
Wrapping Up
Mastering a roblox networking tutorial isn't about memorizing every single function; it's about shifting your mindset. You have to stop thinking about your game as one single program and start thinking about it as a conversation between many different computers.
The server is the host of the party, and the clients are the guests. The guests can ask for a drink or ask to play a song, but the host is the one who actually goes to the fridge or changes the music.
It takes time to get the "feel" for what should be on the client and what should be on the server. You'll make mistakes, you'll accidentally let players teleport across the map, and you'll definitely forget to use a RemoteEvent at least once. But that's all part of the process. Keep experimenting, keep testing with the "2 Players" mode in Studio, and eventually, networking will become second nature. Happy scripting!