The Khuddaka Nikāya (‘Minor Collection’) is the last of the five nikayas, or collections, in the Sutta Pitaka, which is one of the "three baskets" that compose the Pali Tipitaka, the scriptures of Theravada Buddhism. This nikaya consists of fifteen (Thailand), seventeen (Sri Lanka), or eighteen books (Burma) in different editions on various topics attributed to the Buddha and his chief disciples.
The word khuddaka in the title means ‘small’ in Pali and is derived from the Sanskrit kṣudraka (kshudraka). Nikāya is ‘collection’ in both languages; however, Mahayana Buddhists use āgama for this meaning. Kṣudraka Āgama is therefore the Mahayana equivalent of Khuddaka Nikāya.
Professor Hirakawa Akira has stated that the Khuddaka Nikaya represent a stage in the development of the Pali Canon / Agamas in which new material was not added any more to the rest of the Sutta Pitaka, but was added to a Khuddaka Pitaka instead. This Khuddaka Pitaka was the repository for materials that were left out of the four Agamas/Nikayas (the Digha Nikaya, Majjhima Nikaya, Samyutta Nikaya and Anguttara Nikaya) and thus included both early and late texts. Some of the schools that included a Khuddaka Pitaka in their canons were the Mahisasaka, Dharmaguptaka and Mahasanghika. The Khuddaka Nikaya of the Theravada school is the only extant example of such a Khuddaka Pitaka.
This nikaya contains some or all of the following texts:
The introduction to the Sumangalavilasini, the commentary on the Digha Nikaya compiled in the fourth or fifth century by Buddhaghosa on the basis of earlier commentaries that no longer survive, says that the reciters of the Digha listed 2-12 in this nikaya, while the reciters of the Majjhima Nikaya listed 2-15. Later, it gives a listing of the contents of the Canon also found in the introductions to the commentaries on the Vinaya and Abhidhamma Pitakas, which gives 1-15 for this nikaya, though it also includes an alternative classification in which the Vinaya and Abhidhamma are also included in this nikaya, so that the five nikayas are a classification of the whole Canon, not just the Sutta Pitaka. Scholars conclude on the basis of these lists that 13-15 were added later, and 1 later still.