All I know is there are several different types. Bruce Lee wasn't a master of kung fu like everyone thinks. He made up a mixed martial art- Jeet Kun Do. There's is also Drunken Boxing which is a form of Kung Fu and it is really awesome. I think they have some videos on YouTube.

I know Keanu Reeves knows it.

I've taken training in Karate, Hapkido, Tae kwon Do, and Kung Fu over the years. Of all of them, I enjoyed Kung Fu the most. When I first started taking Kung Fu, I was amazed when I was able to feel the inner energy flowing through me. It felt incredible, and I just wanted to practice more and more because of how amazing the movements felt. I told my trainer what I was experiencing and he said it was the chi I was feeling flowing through my body. He said it had been the same reason that he was drawn to it years ago, and that that was what the Chinese Martial arts were all about. He said the Japanese and Korean martial arts were what are referred to as "hard" martial arts, and are force against force. Whereas the Chinese martial arts are "soft" martial arts and are about the internal energy flow. It was just phenomenal. I remember when he taught me a blocking technique that was simply effortless. At first it was simply incomprehensible to me that so little effort would actually protect me and was so effective. He was patient and we practiced in slow motion a few times, then gradually speeded up. Before long he was throwing full force strikes to my head and chest, and I was totally deflecting the blows with virtually no effort at all. I'd never experienced anything like it in any of the other fighting styles I'd studied. Another technique I learned was how to duck a blow. Again, the technique was very simple, and as I felt the energy as it was shifting within my body the movement felt nearly effortless. I felt like the entire exercise was done in slow motion. I made a comment about this when we'd finished, and the instructor put his hand on my shoulder and told me that, no, he had been striking full force at my head, at full speed. He turned to the side and showed me, and I was just amazed. He was striking fast and hard. He asked if I would like to try it again, and I said "with you striking like that...?" He told me to trust myself, I had been doing it a few minutes earlier, and doing just fine. So, we did, and as soon as I sensed his movement, I went into the techique I had learned and it seemed as if time just slowed down for me as I successfully avoided perhaps a dozen blows, one after another. For me Kung Fu has been the most effective, the most enjoyable, and the most amazing martial art that I've ever experienced.

... a fair amount ... read my profile ... There are several thousand officially recognized King Fu styles and many, many more family ("Gar") styles. Of all the official styles, Hung Gar has the most students world wide ... and has been made even more popular by Jet Li's portrayal of the original Master Hung ... in the movie trilogy, "Once Upon a Time in China -1, 2, & 3"

A lot

Not much, because I only took 8 lessons, lol :D

It lets you fight cows.

I've seen Kung Fu Panda. And I LOVED it. As for Kung Fu, I think it's a cool art of fighting, and I would love to learn it, except I don't see myself excelling in that area. I still await a confirmation from Master Oogway. :) I think it's an effective way to eliminate your opponents, and also aesthetically.