An interactive applet and associated web page that demonstrate the concept of an arc. The applet shows a circle with part of it highlighted to identify the arc. Each endpoint of the arc can be dragged to resize it. The web page ahs definitions and links to the properties of an arc.

Applet can be enlarged to full screen size for use with a classroom projector. After use in the classroom, student can access it again from any web browser at home or in the library with no login required.

This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.