In general, kickboxing refers to a sport based on kicking and punching and historically it is developed from karate, Mauay Thai and western boxing. In general, people practice it for self-defense, general fitness, or as a contact sport. This is, of course, a very broad description. This definition simply doesn't do the sport justice.
My first time kickboxing somewhat kicked my okole (butt) but it was tons of fun. What is good about it is that the classes can incorporate people of different fitness levels so it's okay to go to class when you've never done anything like it before. I did and had a blast! And if you don't have your own equipment, such as gloves, Steve has extras available. Check out Steve's website for a schedule of all the classes available http://www.thedojo-hawaii.com/