Luau Course

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Introduction ​

Written: 2026-10-14

Learning objectives ​

  • Explain what a program is in your own words.
  • Describe how the computer runs source code line by line.
  • Read a simple error message and find the line number.
  • Split a small task into clear ordered steps.

Prerequisites ​

  • You need no programming experience. This is the starting point.
  • Skim the course home so you know where you are in the course.

What programming is ​

A program is a set of instructions you write for a computer to follow.

Source code means the text you write. You write it in a programming language. A programming language gives you strict words and rules the computer can follow.

In this course you write Luau. Luau is the scripting language creators use in Roblox Studio. You will run your Luau code inside Roblox Studio.

Write small exact commands. The computer obeys them without guessing your intent.

How source code runs ​

You write source code as text. The computer reads it and performs each action in order.

Think of a recipe. You list steps. The cook follows step one, then step two. Code works the same way.

Roblox reads your code when the game runs. It starts at the top and moves down line by line. Each line tells it to do one thing.

Here is one tiny example. Do not run it yet. You will type this in the Command Bar in Your First Script.

luau
print("Hello!")
txt
Hello!

The word print tells Roblox to show a message. A message is text you want to see while testing. Roblox shows that message in the Output window, which displays messages from calls to print. You will learn to read that window soon.

What errors are and how to read them ​

An error means Roblox could not follow your instruction. This is normal. Every programmer sees errors daily.

There are two simple kinds. A typo stops Roblox before it runs. A bad action stops Roblox while it runs. In both cases Roblox tells you.

Read an error from left to right. Look for three parts: the place, the line number, and the reason. For example, Script:2: missing argument points to line 2 and tells you something is missing.

Do not panic when you see red text. Read the line number first. Open that line. Fix one thing. Run again.

Thinking in steps ​

Algorithmic thinking means thinking in small ordered steps. An algorithm is just a plan with an order.

You already use algorithms. You follow steps to brush your teeth and to tie shoes. Code needs the same care.

Keep each step tiny and clear. Say who does what and what happens next.

Bad step: "make the game fun." Good steps: "show a message," then "wait for the player," then "open the door."

You will learn the Luau words for steps like variables and loops in variables and values and later Level 1 chapters. For now you only practice the thinking.

Breaking problems into steps ​

Take a small problem. Write the goal in one sentence. List the steps in order. Check each step.

Example goal: greet the player when the game starts.

Steps:

  1. Start the game.
  2. Show the words "Hello!".
  3. Stop.

That is enough for Level 0. Later you will turn each step into real code.

Ask three questions for any task:

  • What starts the task?
  • What changes?
  • How do you know it worked?

If you cannot answer, split the task again. Smaller steps are easier to test.

Common mistakes ​

  • Wrong: You try to memorize every word before you start. Why: Memory fades without use. Fix: Read one idea. Try it in Studio. Repeat.
  • Wrong: You read only the red error color and miss the line number. Why: Color grabs your eyes first. Fix: Force yourself to read the line number, then open that exact line.
  • Wrong: You write five steps in one giant step. Why: Big steps hide smaller choices. Fix: Split any step that uses the word "and" into two steps.

Exercises ​

  1. Say in your own words what a program is. Use one or two short sentences.
  2. A friend says the computer "understood what I meant." Rewrite that idea in a correct way.
  3. Break "say hello to a friend" into four or fewer tiny ordered steps.
Solution 1

A program is a list of exact instructions. The computer follows them in order.

Solution 2

The computer follows the exact words you wrote. It does not guess your intent. You must fix the words to change the result.

Solution 3
  1. Walk to your friend.
  2. Look at your friend.
  3. Say "Hello!".
  4. Wait for the answer.

Summary ​

You write exact steps as source code. Roblox runs those steps in order. Errors point you to a line and a reason. Small steps make problems easy.

Next, open Studio and Environment and meet the tools you will use.