function with ... as its parameter?

Any one know what is means by

void Log(int nLevel,LPCTSTR lpszFormat,...)
{

}

May I know what can ... inside the above function refering to?

LPCTSTR is nothing but a format string..This string must be null-terminated.
The arguments to be inserted into the pszFormat string. e.g:-
LPCTSTR pszFormat = TEXT("%s %d + %d = %d.");
Now pass it as parameter in the log function...