Window decoration

In graphical user interfaces, the window decoration is a part of a window in most windowing systems.

A windows decoration typically consists of a title bar, usually along the top of each window and a minimal border around the other three sides. On Microsoft Windows this is called "nonclient area".

In the predominant layout for modern window decorations, the top bar contains the title of that window and buttons which perform windowing-related actions such as:

The border exists primarily to allow the user to resize the window, but also to create a visual separation between the window's contents and the rest of the desktop environment.

Window decorations are considered important for the design of the look and feel of an operating system and some systems allow for customization of the colors, styles and animation effects used.

A window border is a window decoration component provided by some window managers, that appears around the active window. Some window managers may also display a border around background windows. Typically window borders can be used to provide window motion enabling the window to be moved or resized by using a drag action. Some window managers provide useless borders which are purely for decorative purposes and offer no window motion facility. These window managers do not allow windows to be resized by using a drag action on the border.

A title bar is a graphical control element and part of the window decoration. provided by some window managers. As a convention it is located at the top of the window as a horizontal bar. The title bar is typically used to display the name of the application, or the name of the open document, and may provide title bar buttons for minimizing, maximizing, closing or rolling up of application windows. Typically titlebars can be used to provide window motion enabling the window to be moved around the screen by using a drag action. Some window managers provide titlebars which are purely for decorative purposes and offer no window motion facility. These window managers do not allow windows to be moved around the screen by using a drag action on the titlebar.

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