Migraines are one of four types of primary headaches, and they come in two forms, those with an aura and those without. The other three primary headaches are tension headaches, cluster headaches and, the catch-all type known as, other primary headaches. These include things like exercise induced or cough induced headaches.No one knows for sure the exact mechanisms that cause migraines, but we do know it’s a neurobiological disorder, which I’ll get to in a minute..To begin with, let’s look at headaches in general. Headaches come in two forms, primary and secondary. A primary headache is one where the headache is the problem, and as such, is the cause of your symptoms. A secondary headache is one where the headache is the result of something else, like a stroke or a hangover.

via The Science of Migraines.