The Hungarian Notation was invented by Charles Simonyi from Microsoft. It is a naming convention. It is a reminder of the type of a variable. The Handles have an 'h' prefix (e.g. hWnd) - which is a shorthand notation for the 'handle_of_Window'. Likewise 'nLines' is a short hand notation for the 'number_of_lines', 'pData' is a short hand notation for the 'pointer_to_data'. These notations produce the readable code.