4. 자료형

Value Type	Description
nil	Used to differentiate the value from having some data or no(nil) data.
boolean	Includes true and false as values. Generally used for condition checking.
number	Represents real(double precision floating point) numbers.
string	Represents array of characters.
function	Represents a method that is written in C or Lua.
userdata	Represents arbitary C data.
thread	Represents independent threads of execution and it is used to implement coroutines.
table	Represent ordinary arrays, symbol tables, sets, records, graphs, trees, etc, and implements associative arrays. It can hold any value (except nil).

예제

print(type("What is my type"))   --> stringt=10print(type(5.8*t))               --> numberprint(type(true))                --> booleanprint(type(print))               --> functionprint(type(type))                --> functionprint(type(nil))                 --> nilprint(type(type(ABC)))           --> string

When you build and execute the above program it produces following result on Linux:

stringnumberfunctionfunctionbooleannilstring

출처 : http://www.tutorialspoint.com/lua/lua_data_types.htm