Subdural hematoma most commonly results from –
Subdural hematoma                →  Injury to cortical bridging veins
Epidural hematoma                 →  Injury to the middle meningeal artery
Subarachnoid hemorrhage       →  Rupture of berry (saccular) aneurysm
Rupture of intracranial aneurysm
Rupture of cerebral AVM
Injury to cortical bridging veins
Hemophilia