Knowledge skills are nearly always based off of Intelligence. At a low level they can be represented by common sense and experience, but at higher levels they generally require some level of book learning.
- Alchemy - Knowledge of making, using and identifying alchemical mixtures.
- Arcana - Knowledge of magical things.
- Common - Knowledge of common 'human' society and culture.
- Dungeoneering - Knowledge of things and places found underground.
- Engineering - Knowledge of how to build mechanical and architectural things.
- Geography - Knowledge of physical terrain and also where things are.
- History - Knowledge of what has happened in the past.
- Medicine - Knowledge of medicine and healing people.
- Nature - Knowledge of plants and animals.
- Nobility - Knowledge of noble etiquette, structures and who is who.
- Philosophy - Knowledge of the theories of morals and ethics.
- Planes - Knowledge of the metaphysics of the outer planes.
- Religion - Knowledge of cults, priests and gods.
- Warfare - Knowledge of military strategy.
Knowledge skills may have specialisations. Geography and History for example will have specialities for particular regions. If you have never been to, or read about, a place then you won't know anything about it until you also pick up a speciality in that area.
Knowledge Common is had by almost everyone to some degree. It covers human, and human-like, culture, civilisation and society.
- Magic Theory - Knowledge of how academic magic works, for the purpose of learning and inventing spells.