This document describes five widgets that have been developed at the Human-Computer Interaction Laboratory of the University of Maryland. These widgets are a range selection slider, a two-level alpha-slider, a secure switch , a tree viewer and a treemap viewer. The last two use the same tree representation and can be used as alternate visualizations of the same hierarchy. In addition, a system for widget specification is introduced and each widget is specified using this system. (Also cross-referenced as CAR-TR-734) (Also cross-referenced as ISR-TR-94-69)