What are the three types of kimchi?

Can you explain to me the different types of kimchi that exist? I've heard there are three main types, but I'm not sure what they are. Could you give me a brief overview of each one? Perhaps you could start with the most common type and then move on to the other two. Also, if possible, could you mention any unique characteristics or flavors that distinguish each type? I'm really curious to learn more about this traditional Korean dish.