X-Motif UIL Table (.uil)
The UIL file extension stands for User Interface Language and is associated with the X-Motif UIL Table. It is a plain text file format used by the UIL compiler to create user interfaces for the X Window System. UIL files define menus, buttons, dialog boxes, and other graphical user interface components. Introduced by The Open Group, this format allows developers to describe the initial state of a user interface, including widgets, resources, and callbacks. The UIL file is compiled into a UID file, which can be accessed by Motif Resource Management functions within an application.