The system can use only one cursor at a time, so windows must create and destroy cursors as each windows gains and loses the keyboard focus. If an application attempts to use more than one cursor at a time, the results can be unpredictable and might affect other applications.

An application creates a cursor by calling WinCreateCursor. Generally, this is done when a window gains the keyboard focus. The application specifies the window in which to display the cursor, whether it be the desktop window, an application window, or a control window. An application destroys a cursor by calling WinDestroyCursor- when the specified window loses the keyboard focus, for example.