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Roblox Studio, from a blank baseplate to a published obby

CodeWithPurpose lessons that build one real obstacle course in Luau, and explain the engine underneath it as you go. Fourteen chapters, and Studio is free.

All CoursesUdemy Roblox Course
Student building a game on a laptop

1. Inside Studio

3 chapters

What the editor actually is, the live tree of objects behind it, and the handful of properties that decide what a block does.

Foundations

What Studio Actually Is

Studio looks like a level editor, and it is also a server, a client, and a publishing pipeline running together on your laptop. Notice which of those you are looking at before you write a line, because each one fails differently.

8 min read

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FoundationsInteractive

Everything Is an Instance in a Tree

The Explorer looks like a list of folders and is really your running game, live, with every object in it. Click down through the tree and watch the path assemble itself exactly as a script would have to write it.

9 min read

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FoundationsInteractive

A Part, and the Four Properties That Matter

A new block falls to the floor, drifts through walls, or hangs in mid-air, and a handful of checkboxes decide which. Toggle each one and watch the same part stop being the same object.

9 min read

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2. Scripting in Luau

4 chapters

Where code goes, what it can reach, and the fact that your game is running on two computers that do not agree by default.

ScriptingInteractive

Where Code Goes, and Where It Runs

The same eight lines of Luau will run for everyone, run for one player, or never run at all, decided entirely by which object you dropped them under. Move one script between four parents and see which of them start it.

10 min read

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ScriptingInteractive

Names, Values, and the Only Two Things That Are False

Luau agrees with most languages about what a variable is and disagrees sharply about what counts as false. Hand it a zero and an empty string, and find that it treats both as true.

10 min read

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Scripting

Reaching Into the Tree From Code

script.Parent works beautifully until somebody renames a part, and then it fails with a message about indexing nil. Compare the four ways to find an object and see which survive a part that has not loaded yet.

10 min read

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Scripting

Two Computers, One Experience

Your obby runs on Roblox's server and on every player's own machine at once, and by default they disagree. Move a part from a LocalScript, watch it move for exactly one person, and see why a killbrick cannot live there.

11 min read

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3. Events, and Doing Something Once

2 chapters

Nothing polls in Roblox — the engine tells you. Then it tells you forty more times, and you deal with that.

ScriptingInteractive

Code That Waits to Be Told

Nothing in an obby sits in a loop asking whether a player has arrived — the part announces it. Connect a function to Touched, walk across the part once, and count how many times it actually fired.

10 min read

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Scripting

Doing It Once, When the Engine Says It Forty Times

One step onto a platform can fire Touched forty times in a quarter of a second, and now forty copies of your handler are running at once. Add a single boolean and watch thirty-nine of them turn around at the door.

10 min read

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4. Building the Obby

3 chapters

The three classic obstacles, written properly: a laser that kills, a platform that drops you, and one you can only pass one way.

ObbyInteractive

The Laser That Actually Kills

A killbrick is four lines, and three of them exist to answer the question Touched refuses to: whose leg was that. Trace one touch from the limb it hit all the way back to the player it belonged to.

11 min read

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Obby

The Platform That Drops You

Making a part vanish is two properties; making it come back reliably is where every bug lives. Step on the naive version twice in a second and watch the platform stay gone for the rest of the round.

11 min read

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ObbyInteractive

Solid From Above, Empty From Below

A one-way platform compares two heights and flips one property, and that version falls apart the moment a second player joins. Drag one player through it, add another, and watch a single shared property fail them both.

12 min read

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5. Shipping It

2 chapters

Reading what the engine says when it breaks, and the settings that stand between a finished place and a friend being able to open it.

ScriptingInteractive

Reading What Went Wrong

The Output window names the script, the line, and the exact object that was nil, and most people close it. Read three real Roblox errors and find the single word in each that identifies the problem.

11 min read

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Shipping

Getting It in Front of People

Publishing is one menu item, and four settings underneath it decide whether a friend can actually open what you made. Walk each one, in the order that stops a finished obby from being unplayable.

10 min read

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Open source

Your chapter goes here

Every chapter here was written by a student. Propose your own topic, or fix one that confused you. Drafts stay invisible until they are ready, so nothing you start can break the site.

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