Comments

A comment is text that the Luau parser ignores at runtime.

Single-line Comments

You can define single-line comments with a double hyphen (--) anywhere outside a string. Single-line comments extend to the end of the line.

Use single line comments for in-line notes. If the comment spans multiple lines, use multiple single-line comments.

You can add and remove single-line comments in the Script Editor with the keyboard shortcut Ctrl/ (⌘/).

-- This condition is really important because the world would blow up if it
-- were missing.
if not foo then
    stopWorldFromBlowingUp()
end

Block Comments

You can define multiline block comments with double hyphens and double brackets (--[[]]). Use block comments for documenting items:

• Use a block comment at the top of files to describe their purpose.
• Use a block comment before functions or objects to describe their intent.

--[[
    Shuts off the cosmic moon ray immediately.

    Should only be called within 15 minutes of midnight Mountain Standard
    Time, or the cosmic moon ray may be damaged.
]]
local function stopCosmicMoonRay()
end

If necessary, you can nest multiple brackets inside a block comment using the same number of equal signs in both the beginning and ending bracket:

--[=[
    In-depth detail about cosmic moon ray: [[[TOP SECRET]]]
]=]

TODO Comments

Roblox Studio supports special TODO comments. Studio bolds any text following TODO (until broken by a space):

-- TODO: Finish the function below so that it actually does what its name implies.
local function stopWorldFromBlowingUp()
end

Use TODO comments to keep track of and communicate issues within your code.