system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What exactly is a headache and what causes it?

1. What causes them?
2. How do they go away?
3. My head is killing me....
gpt
1. There are many different headaches caused by many different things. The good news is, it's probably not a tumah. The brain itself can't feel anything. If you have a headache it is most likely caused by tension of the blood vessels in the head or tension of the muscles supporting your neck and head. 

2. Excedrin for big kids like you. The combination of acetominophen and caffeine really is the best over the counter option. If it's a tension headache, anything containing ibuprofen will also do in a pinch. However, the quickest non medical home remedy is to lightly grasp a  good amount of hair from both sides of your head near your temples and pull outward. Lightly at first and increasing until the pain subsides somewhat.

3. Life is pain.