Ahimsa is a Sanskrit term that means non-violence
(the avoidance of violence - himsa).

Ahimsa is imperative for Yoga practitioners. Ahimsa is one of the 5 Yamas which make up the code of conduct and is the first of the eight limbs of Yoga.
Vegetarianism and moral living are observed as aspects of Ahimsa. According to the classic manual of Hatha Yoga Pradipika, Ahimsa is an obligation.

Ahimsa is an ancient Indian rule (Hinduism, Buddhism and especially Jainism) that prohibits the killing or injuring of living beings.

The exact origins of Ahimsa are unknown and the earliest references to Ahimsa come from the texts of the Historical Vedic Religion as long as the 8th century BC where Ahimsa only meant the "non-injury" and 'not mortal', but later it relates to NON-VIOLENCE to Animals and all Beings.