Ahimsa is usually translated as nonviolence, but the Jain version is a claim about what is alive rather than a rule about how to treat people. Every jiva, every soul, is an entity in its own right, and souls are held to be present not only in humans and animals but in plants and in the bodies of earth, water, fire and air. Beings are classified by how many senses they possess, from the one-sensed upward, and harm to a being with more senses is graver than harm to one with fewer, but nothing is outside the reckoning.
The practical consequence is a discipline of restraint rather than a prohibition that can ever be fully satisfied. Jains hold that living necessarily involves harm and that the obligation is to reduce it. Observant lay Jains are vegetarian; many avoid root vegetables, on the ground that uprooting the plant destroys it and disturbs the organisms in the soil; many filter water and avoid eating after dark. Occupations involving killing or large-scale destruction are traditionally avoided, which is part of why Jain communities have historically concentrated in trade, finance and the professions.
Ascetics take the same five vows in a stricter form: nonviolence, truthfulness, not taking what is not given, chastity and non-possession, held as mahavratas, great vows, where lay people hold them as anuvratas, lesser vows scaled to a life in the world. Monks and nuns of some orders sweep the ground before them as they walk and wear a cloth over the mouth to avoid harming very small creatures.
Ahimsa governs speech and thought as well as action, and it underwrites anekantavada, the doctrine that reality has many aspects and that any single account of it is partial, which Jains present as a kind of intellectual nonviolence, a refusal to do violence to another view by treating one's own as complete.