Wolfram Research
Wolfram Math World: Inscribed Angle
This site provides not only a definition of inscribed angle but also links to related terms.
University of Saskatchewan (Canada)
Finding Arc Length and Central Angle Exercises
This site provides two geometry problems involving circles. One problem has the reader find the arc length given the angle and radius, the other problem has the reader find the measure of the angle given the arc length and radius....
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Proof the Inscribed Angle Theorem
Dr. Math gives a student a hint on how to prove that an inscribed angle is equal to 1/2 the central angle. You should know what the central angle and inscribed angle are to utilize this site.