Ahimsa means to avoid harm. What means to abdicate evil. To abdicate evil means not to do harm to others in thought, word and actions. Simple definition that explain a lot. To the best of our capacity we should never inflict injury on another living being.
--- What is harm? --- Harm means to physical existence ceases, mental development stops, spiritual development stops. So we should avoid actions that cause one of this effects.
--- With what difficulties you may encounter? --- This principle is sometimes interpreted to mean complete non-violence, but if carried to an extreme it becomes very impractical. For example each time we breathe there are microbes which we inhale and kill! To solve this dilemma Anandamurti gives suggestions, saying that in selecting our diet we should choose the food where consciousness is less developed before killing highly developed creatures. Should not be any dogmatism in this thinking. Rationality tells us that in order to save the lives of more developed consciousness in the food used less developed. From the other hand nothing bad if there is a question of survival or saving the life and you will eat meat as the only one source of food. So always think twice if there is a way to avoid killing. All other cases (to receive pleasure, for fun ...) are considered as harm. Check the animal world, all living beings kill only from the necessity. Another problem is the question of self defense. Life is a struggle. Here Anandamurti says that to defend oneself against an aggressor or against an anti-social person is justifiable. Even if you use force, your intention is to save and protect life, not to cause pain or block the mental, physical or spiritual progress of that person. Aggressor will be a person who (old meaning): - wants to take away your land so that you will starve to death - wants to set fire to your house - wants to outrage your wife - stands with arms in hand against you - wants to poison you - wants to rob you Once again if there is a way to protect yourself and not to deprive the life of another living being then it's better.
--- Benefits --- - you will have no/less aggression and fear (What is the same in nature). From animal life: if you have an aggression then animal will consider you as enemy, if you have a fear then animal will consider you as victim, if you will have not both of this then you will be considered as a friend.
--- In which chakra it is located? --- Manipura chakra has an emotion to cause harm to others. It calls sadism.
--- How to practice? --- Treat with respect to the whole creation and everything will treat you with respect! Meditation as a skill to help ;) Levels of practice: Thoughts -> words -> physical
Thoughts: watch -> catch -> fix Negative thoughts you need to change to positive. For example, it's not my enemy, it's my friend, I want him to be happy. if you quarrel with someone - make friends if you take offense at someone - sorry if you envy someone - let go, rejoice
Words: watch -> catch -> fix Cultivate the habit of being polite and correct
Physical: think deeply about your living on this planet (food, clothes ...). Life in such way to harm others as less as you can!
--- Definition --- https://www.yogapedia.com/definition/5236/ahimsa