Most Common Headache

Tension Headaches:

Causes:
Since a tension headache is so common, the causes are pretty widespread. They're caused by anxiety, eye strain, caffeine, food, poor rest, bad posture, stress, hunger, or just about anything else you change in your daily schedule. Tension headaches are also usually the type of headache you end up with after a night of alcohol. Essentially, if something is abnormal about your day, whether it's a late lunch or a series of deadlines at work, a tension headache might pop up.

Treatment:
Tension headaches are usually best handled with over-the-counter painkillers like aspirin or ibuprofen before the pain gets severe. Those aren't cures, but they make the pain go away for a while. In general, your best bet is to rest and relax until the headache goes away. Even a hot pepper may provide some relief. If your headaches are common enough, your doctor may have other solutions. Otherwise, it's good to find your triggers, minimize them, and fight back. If a headache comes from stress, meditation may help, if you're hungry, then eat. If it comes from eyestrain, get away from the computer for a while.

Prevention: Tension headaches are best prevented by tuning your routine to minimize potential triggers. It's a little trial-and-error to find the exact cause of a tension headache, but if you know they come around when you're stressed, hungry, or tired, then you can work on preventing them. Even certain food allergies can trigger a headache.

Migraines:

Causes:

According to the Mayo Clinic, the exact causes of migraines are still unclear, though it's thought that genetics and your environment can both cause migraines (around 70 percent of migraine sufferers have a hereditary influence). It's thought that hormonal changes, stress, unusual sensory stimuli (like weird odors or bright lights), changes in sleep patterns, and even a change in the weather all act as potential triggers for a migraine.Your diet can also play a roll in migraines.

Treatment:

Migraines are a mixed bag for treatment options, but doctor-prescribed triptans(like Imitrex, Zomig, Maxalt) are the most commonly effective pain reliever for people when over the counter solutions like Aspirin don't work. In the middle of a migraine stretching can relieve some symptoms. If all else fails, when you're waiting out the pain, a cold head wrap may provide a little relief.

Prevention:

While migraines may be hereditary, they're still usually caused by triggers, and it's typically recommended that you narrow down those triggers and avoid them. Again, a headache diary can be helpful in narrowing down those triggers. It's also thought that light exercises like walking can help prevent migraines. While inconclusive, certain remedies like butterbur (a plant extract), magnesium (found in wheat bread, almonds, spinach, and more) and riboflavin (found in cereals, pastas, sauces, and more) may be effective in reducing the frequency of attacks. Getting the exact amount of good sleep every night is also thought to help decrease the occurrences of migraines.
Sinus Headaches:

Causes:

A sinus headache comes about when the sinus gets inflamed, usually from an allergic reaction (that causes sinus congestion) or infection (like a cold or flu). As the sinuses get inflamed, the inflammation causes swelling and increased mucus so everything gets blocked up.
Treatment:

Treatment of a sinus headache is a tricky business because you're attacking on two different fronts: the pain relief of the headache itself, and treating the sinus infection. According to WebMD, the best treatment is usually an antibiotic to deal with the infection and antihistamines to help you deal with the symptoms. In the heat of a sinus headache, drinking lots of fluids is key to recovery. A humidifier or salt water nasal spray is often helpful.
Prevention:

Since sinus headaches often come from two sources, prevention is all about lowering your exposure to both. For allergy related headaches, humidifiers, nasal sprays steam, and neck stretches are thought to help. Certain dietary supplements may also help,

including bromelain (found in pineapple stems), and quercetin (brewed black or green teal, kale, red onions, and others). Lowering your contact with allergens is also key to prevent sinus infections.
Of course, if the infection comes from a cold or flu, then your best idea is to avoid getting sick. A good amount of sleep, washing your hands, and cutting out cigarettes and alcohol are the best way to prevent illness. That said, a little steam is good for preventing colds as well.