Oregon State University
Calculus Quest: Left and Right Hand Limits
Find out how to determine if a limit exists and what its value is. This site contains an interactive limit finding exercise of a particular graph. Be sure to continue to the next page by following the small blue arrow under the exercise...
University of Minnesota
University of Minnesota: Calculus Graphics: Limits
This page offers visual aids to understand the existence of a limit to a function. The site briefly discusses left and right-hand limits.