Module is a source file containing a set of variables/functions/classes you want to include in your program.
Assume there is a module file named

func test_module()
    print("this is test");

#Include command
You can include the above module file in your program by using #include as follows:
#include "" //include

        test_module();//call the function in the file

The search path of #include is current directory where your program(main function) is located, and the relative path is also available:
#include "include/"
#include "../base/"

You can also use the absolute path to include the file:
#include "D:\\myworks\\"

The file can be included several times, but it will be loaded only once.