For the lazy, Wikipedia:

>In the Vedic religion, Ṛta (/ɹ̩ta/; Sanskrit ऋत ṛta "order, rule; truth; logos") is the principle of natural order which regulates and coordinates the operation of the universe and everything within it. In the hymns of the Vedas, Ṛta is described as that which is ultimately responsible for the proper functioning of the natural, moral and sacrificial orders. Conceptually, it is closely allied to the injunctions and ordinances thought to uphold it, collectively referred to as Dharma, and the action of the individual in relation to those ordinances, referred to as Karma – two terms which eventually eclipsed Ṛta in importance as signifying natural, religious and moral order in later Hinduism. Sanskrit scholar Maurice Bloomfield referred to Ṛta as "one of the most important religious conceptions of the Rigveda, going on to note that, "from the point of view of the history of religious ideas we may, in fact we must, begin the history of Hindu religion at least with the history of this conception"