What is epilepsy?

The nature of seizures is highly variable,1,3,5 for example:
Classifying seizures helps, for example, when selecting treatments.3,6,7
Focal onset
Start in one area of the brain
May account for 60% of all epilepsies8
Generalized onset
Affect both sides of the brain
Unknown onset
Seizures that are not controlled by treatment can interfere with life, e.g. affecting education, employment, and relationships.4

Quantifying epilepsy