ACD/Structure Drawing Applet (ACD/SDA) is a complete structure drawing, editing, and visualization tool written in pure Java that can be incorporated into HTML documents. The applet can be used for composing substructure queries to databases and visualizing results. Unlike platform-dependent plug-ins or ActiveX controls, the applet runs in the same way on any hardware platform or operating system - the only requirement is a Java-compatible browser such as Netscape 4.0 or later or MS Internet Explorer 4.0 or later.