As in most programming languages, the name of an identifier must be a sequence of letters, digits, or underscore symbols, and may not begin with a digit. The lua interpreter is lettercase sensitive so variables with uppercase and lowercase names are distinct and separate from each other. It is not permissible to use keywords as variable names.
Avoid choosing names that begin with an underscore followed by uppercase lettersEdit
Avoid choosing names that begin with an underscore followed by uppercase letters. These names are reserved for special uses.
Foreign language lettering is permitted within variable namesEdit
It is permissible to use foreign language lettering for variable names, providing that these characters are defined as letters within the locale. However, this makes the code non portable to systems that do not support locale, or on systems that have a different language settings than the program was coded for.