The Win32 API provides general window styles and class-specific window styles. The general windows styles are represented by constants that begin with the WS_ prefix; they can be combined with the OR operator to form different types of windows, including main windows, dialog boxes, and child windows. The class-specific window styles define the appearance and behavior of windows belonging to the predefined control classes such as edit controls and list boxes. This overview describes the general window styles.
An application usually sets window styles when creating windows. It can also set the styles after creating a window by using the SetWindowLong function.