Causes of Headaches

What causes headaches? Asking that question is like asking, "What's for breakfast?". It seems like a simple question, but you have now opened yourself up for an onslaught of follow-up questions: "How hungry are you?", "How do you like your eggs?", "Do you even eat eggs?". So, in asking the question, "What causes headaches?", you need to start looking at the metaphoric "main course" - What kind