From Rigpa Wiki
ཆོས་མངོན་པ་, མངོན་པ་, chö ngönpa, Wyl. chos mngon pa) — the third of the three pitakas, or collections (literally ‘baskets’), into which the Buddhist teachings are divided. This pitaka, which is associated with the training in wisdom (Skt. prajñā), defines many of the topics mentioned in the sutras, and arranges them in classifications, such as the five skandhas, twelve ayatanas and eighteen dhatus, thereby providing tools for generating a precise understanding of all experience.
Artemus Engle writes:
- Often viewed as little more than a dry and uninspiring catalog of lists and definitions, this material is in fact a repository of the fundamental concepts and ideas that inform all of the major Buddhist philosophical schools and traditions. Great Mahayana figures like Nagarjuna and Asanga should properly be seen as presenting a critical analysis of the early realist tendencies in Buddhist thought, rather than positing views that reject the very framework on which all Buddhist philosophical theories are constructed. On a more practical level, Abhidharma literature contains the subject matter that allows one to investigate and learn with minute precision every aspect of the three Buddhist trainings of morality, one-pointed concentration, and wisdom. 
- higher knowledge
- inner science
- special knowledge
- Artemus B. Engle, The Inner Science of Buddhist Practice: Vasubhandu's Summary of the Five Heaps with Commentary by Sthiramati, Ithaca: Snow Lion, 2009
- Trungpa, Chogyam, Glimpses of Abhidharma. Boston, Mass.: Shambhala, 2001.
- Guenther, Herbert V. Philosophy and Psychology in the Abhidharma. Rev Sub edition. Delhi: Motilal Banarsidass, 2011.