What is Kendo?
Taken from the Wikipedia article on Kendo:
“Kendo (剣道), meaning “Way(道) of The Sword(剣)”, is a modern Japanese martial art of sword-fighting based on traditional Samurai swordsmanship, or kenjutsu. Kendo is a physically and mentally challenging activity that combines strong martial arts values with sport-like physical elements.”
The rest of the article can be read here.
The Southern California Kendo Federation (SCKF) also provides a good reference page on kendo.