1. A computer-readable medium encoded with a computer program for authoring a live component comprising: a rules based editor configured to edit an equation related element, the rules based editor using at least one rule related to a pre-built application module, the pre-built application module included in a viewer module, the viewer module including rendering related instructions and equation evaluation related instructions, the edited equation related element configured to be included in a component description file; the combination of the viewer module and the component description file configured to be used to display a version of the equation related element that is analytically related to second equation related element.