markup file expressing ui controls and behavior in human readable form the ui binary file is utilized in a runtime environment on a computing device as a source of a binary instruction stream the stream can be efficiently processed by an interpreter on the device without needing validation between loading and rendering the ui the encoding places much of the representation into an object and script section of the ui binary file the interpreter runs this section without it being entirely resident in the device 39 s memory to minimize the memory footprint at runtime operation code streams contained in this section are used to build ui objects and implement scriptable behavior for manipulating the ui objects to render the ui on the device with the designed behavior application_number US 3709708 A description fig1 and 2 show illustrative computing environments respectively indicated by reference numerals 100 and 200 in which the present compact portable and efficient ui control tree representation may be implemented in environment 100 a desktop pc 105 is representative of a class of devices characterized by relatively high levels of computational power memory and storage by comparison in environment 200 a portable electronic device 205 such as a media player smart phone mobile phone pda personal digital assistant handheld game player or the like has relatively lower levels of capabilities however in its binary form the present ui control tree representation is arranged to be portable across differing platforms and operating system architectures.