The second book of the Khuddakanikāya of the Sutta Pitaka.
It includes verses (gāthā) collected together from various books in the Canon, but contains hardly any from the Jātaka collection, or directly derived from the Suttanipāta.
The present text of the Dhammapada contains four hundred and twenty-
So far, five recensions of the Dhammapada have been discovered. (For details see Law: Pāḷi Lit., pp.215 f).
The commentary on it is called the Dhammapadaṭṭhakathā.