For those that haven't had any experience with Martial Arts, and in especially Japanese origin arts, let us explain what it is:

Karate is more than an exercise, more than fighting, and more than what you understand from TV or movies. In fact, most of what you know from media is extremely warped idea of what Karate is... KARATE come from a deep past, combining elements of body conditioning, mental awareness, and spiritual alignment. Handed down from the Ancient philosophy of the Samurai, Karate practice is the closest practical continuation of their way of life in modern times, since carrying a sword in daily life is impractical. Karate or the way of the empty hand, has exactly that meaning, defense without weapons. The main difference in Karate vs. other Martial Arts is that fighting is not the main point, but rather how to avoid it, but being confident if the need should arise.  
The main point is balancing the Body, Mind, and Spirit to work together, and not independent of each other.