A HEADACHE: simply means head pain or pain arising from the head.

There are 2 types of headache:
PRIMARY HEADACHES:are those not due to another underlying health problem.These are:
TENSION HEADACHES:most common and what people think as normal everyday headaches.They feel like a dull ache with constant pressure around the front, top and sides of the head as if a rubber band has been stretched around it.90% of population have this type of headache.
Causes:stress,too much alcohol consumption,not getting enough
sleep,skipping meals,depression and dehydration.
MIGRAINES:less common.Pain usually unilateral or bilateral,common in females than males.
CLUSTER HEADACHES:are a third type of primary headache.Pain arises around one eye.

SECONDARY HEADACHES:Result from another medical or neurological condition, include sinus headaches, medication overuse headaches, or headaches that occur because of a head injury, trauma,tumor or systemic diseases.

MANAGEMENT:
PRIMARY HEADACHES:Tension type.Depends on why you have the headache.
Avoid stress,get enough sleep,eat well,drink enough fluids.
You can as well massage the area where you have the pain.
Usually,the common headaches response to analgesics like paracetamol,aspirin or NSAIDs e.g ibuprofen.Other types of primary and secondary headaches,you need a doctor's prescription.

Beware that regular intake of headaches medication could lead to Medication Overuse Headaches a.k.a Rebound headaches and you must see a doctor.