Headaches can vary significantly in number of ways

Headaches can vary significantly in number of ways, including:

Intensity
Location
Frequency
Cause
Primary Headaches
A primary headache is when the headache itself is the main problem. It is not a symptom of an underlying disease or condition. While the pain from primary headaches can be disabling, the headaches are not dangerous. The brain cannot feel pain, so the pain associated with primary headache comes from the inflammation of pain-sensitive parts of the body in and around the neck and head, including:

Nerves
Blood vessels
Muscles
There are several categories of primary headaches. Some of the most common types of primary headaches include:

Migraine headache
Tension headache
Hypnic headache
Cluster headache