O

object
(1) An internal structure that represents a system resource, such as a file, a thread, or a graphic image. See also thread.

(2) A network resource that does not contain any further network resources. It is not necessarily possible to connect to an object.

object type
A measurable entity, such as a processor, disk, or thread.
Open common dialog box
A common dialog box that displays a list of filenames matching any specified extensions, directories, or drives. By selecting one of the listed filenames, the user indicates the file an application should open. See also common dialog box, directory.
overlapped input and output (I/O)
See asynchronous input and output (I/O).
overlapped window
A style of window meant to serve as an application's main window.
owned window
A window that has an owner. Being owned affects the window's position in the Z order and its visibility and can determine when the window is destroyed.
owner window
A window that affects aspects of another window's appearance and behavior.
owner-drawn button
A button with the style BS_OWNERDRAW. Unlike all other button types, an owner-drawn button has no predefined appearance or behavior. Also, the application, not the system, is responsible for painting it. See also button.
owner-drawn control
A predefined control that sends messages to its parent window when it must be drawn.
owner-drawn item
A menu item whose appearance is controlled by a menu's owner window rather than by the system. See also menu item, window.