Can someone explain to me the differences between different types of martial arts please?

Recently I've become interested in learning a martial art (I'm a complete beginner) but I'm a bit confused when it comes to the different types available. I'd really appreciate a summary on the commonly heard one and the differences between them eg. kung fu, wushu, karate, taekwondo. Some sort of advice on what learning each one entails would be much appreciated as well =D (As well as minimum amount of confusion XD)