the concept of the user interface markup languages is primarily based upon the desire to prevent the "re-invention of the wheel" in the design, development and function of a user interface; such re-invention comes in the form of coding a script for the entire user interface. the typical user interface markup language solidifies often re-used program or script code in the form of markup, making it easier to focus upon design of a user interface in an understandable dialect as opposed to focus on function.