page no.79
Creating the window
                     the window class defines general characteristics at a window thus allowing the same window class to be used for creating many different windows.
when you go ahead &create a window by calling create window while the information passed to register class function is specified in dats structure. the 
information passed to the createwindow function is specified as seperatearguments to the function.
hwnd= create window(szAppName,TEXTC"The Hellow"program
)
WS_OVERLAPPEDWINDOW,
CW_USEDDEFAULT,
 CW_USEDDEFAULT,
 CW_USEDDEFAULT,
 CW_USEDDEFAULT,
 NULL,
NULL,
hInstance,
NULL;
                                               The argument marked "Window class name " is szAppName,which contains the string "Hellow win"the name of the windoe class the programm just registered, This is how the window we're creating is associated with window class.
                                               The window created by this programm is normal overlappped wibdow which appears as the "" window style parameter in createwindow ". This style is a combination of several bit stages.