Abstract: The invention discloses a universal window/door frame comprised of a group of components that can be used singularly or in combination to form a plurality of window/door types. The components forming the various window and door types are a frame, sash and T-bar of standard thickness that forms the frame and glass holding elements of the window or door. The hardware defining the window type uses one or more of a plurality of concealed channels contained within the frame. When necessary, access to and use of the channels is obtained by removing material forming the interior wall of the frame providing access to the concealed channel or channels that will be used to define the windows functional components, such as having a screen or a sliding member. Some types, i.e. jalousie and direct set picture windows, do not require the use of the concealed channels. The use of the T-bar provides for the inclusion of various window types having the potential for common glass lines on the vertical and horizontal.