Variable names can be any non-reserved string of letters, digits, and underscores that doesn't start with a digit.
1LETTERS -- valid2a1 -- valid3var_name -- valid4_test -- valid56if -- NOT valid725th -- NOT valid8
Variable names are case-sensitive, so TestVar and TESTVAR are different names. Avoid naming variables with an underscore and all uppercase letters, such as _VERSION, because Luau may reserve them for internal global variables.
It's best practice to spell out words fully. Abbreviations generally make code easier to write, but harder to read. Following common naming practices when naming your variables can help you and others understand their meaning or purpose:
- Use PascalCase names for class and enum-like objects.
- Use PascalCase names for all Roblox APIs. camelCase APIs are mostly deprecated.
- Use camelCase names for local variables, member values, and functions.
- Use LOUD_SNAKE_CASE names for local constants (variables with values that you don't expect to change).
- Don't capitalize entire acronyms within names. For example, write aJsonVariable or MakeHttpCall.
Luau reserves the following keywords, so you can't use them to name variables or functions:
To create a variable and assign a value to it, use the = operator. Put the variable on the left of the = and the value on the right. If you don't put a value, the value is nil.
Variables can have global or local scopes. They have global scope by default, but it's almost always better to create them with local scope because Luau accesses local variables faster than global ones. To give a variable local scope, put the keyword local before a variable's name when you assign a value to it. For more information on Scope in Luau, see Scope.
1local nilVar2local x = 103local word = "Hello"4local reference = workspace.Camera56print(nilVar) -- nil7print(x) -- 108print(word) -- Hello9print(reference) -- Camera10
Assigning Values to Multiple Variables
You can assign values to multiple variables in one line by separating each variable-value pair with a comma. If you have more values than variables, Luau doesn't assign the extra values to any variables. If you have more variables than values, then Luau assigns nil to the extra variables.
1local a, b, c = 1, 2, 32local d, e, f = 4, 53local g, h = 7, 8, 945print(a, b, c) -- 1, 2, 36print(d, e, f) -- 4, 5, nil7print(g, h) -- 7, 88
To change a value of a variable, assign another value to it.
1local x, y = 10, 202print(x) -- 103print(y) -- 2045local x = 10006local y = 20007print(x) -- 10008print(y) -- 20009