The Anguttara Nikaya is one of the five Nikayas (collections) that constitute the Sutta Pitaka, which is part of the Pali Tipitaka, the Theravada Buddhist canon. It is also known as the "Numerical Discourses" or "Gradual Collection". The Anguttara Nikaya is organized numerically, with suttas grouped into eleven books (nipatas) based on the number of items discussed within them. For example, the "Book of the Ones" contains suttas about a single topic, the "Book of the Twos" contains suttas about pairs of things, and so on