Why does humanity need nonviolent communication?
According to data for October 2019, 69 countries are involved in wars . Even in the 21st century, after two world wars, citizens of some countries continue killing citizens of other countries. But any war, like any conflict, ends with negotiations. There are experts who say that if people watched the way they talk to each other, conflicts and wars could be avoided.
For example, in the 1960s the American psychologist Marshall Rosenberg introduced a method of nonviolent communication that he personally used in his practice as a peacemaker and mediator. It says that violence usually leads to human suffering, so we should try not to use it and achieve what we want in other ways. The main thing that is required for this is a mutual understanding of each other's feelings and basic needs.
In 2015 I participated in the Ukrainian-Russian project «Habit of Thinking» and that was the first time when I have heard about this concept. Ukraine and Russia are now at war, and participants from this countries came together to talk about hate speech, prejudices and manipulations - satellites of any conflict. It was very difficult to talk because the war between our countries affected many of us: some of the participants lost their homes, some of them lost friends. Therefore, several experts on nonviolent communication were invited to moderate our communication, they had to make sure that our conversation is constructive and that we won’t fight. After this experience I realized something important: all people are different, and sometimes it is difficult for them to find a common language, but it is not impossible. The main thing is not to win a dispute at any cost, but to reach an agreement, not only to speak out, but also to hear the other side, not to get lost in emotions, but to remain objective. [2, 3]
The basics of nonviolent communication that everyone should know
Let's look at an example to understand the concept of nonviolent communication. Let’s imagine that you are an ESC volunteer who has to live with volunteers from other countries in a shared apartment. You and your neighbors came from different cultures, grew up in different families and lived in different contexts. Let's say one of your neighbors leaves dirty dishes in the kitchen and, to put it mildly, it annoys you. You can say something like “You leave dirty dishes all the time, I get tired of it! You're so dirty, you think only about yourself! Now clean up this mess and never do that again!”, but it will probably provoke a negative response. Let's take a look at this case and think how you can get out of this situation using the rules of nonviolent communication.
People who want to communicate without violence should rely on facts and not give value judgements. "You leave dirty dishes all the time" - this is not a fact, maybe several times your neighbor washed the dishes or washes them, but not when you want this, so the use of the words "all the time" is not very fair in this situation. "You're so dirty, you think only about yourself!” – it is not a fact either, maybe your neighbor just has a different perception of dirty and clean, and you cannot know for sure what the other person is thinking about. "Now clean up this mess and never do that again!” – it sounds like a very strict order and you have no right to order your neighbors.
In this situation you can build a nonviolent message based on the following formula of communication: Observation-Feeling-Needs-Request. Nonviolent communication experts call this formula "giraffe language" (because these animals have big hearts and can see far ahead). According to it, first we should voice our observations - the specific actions that we see and which affect our well-being (without labelling, only facts), then the feelings - what we feel about what we see, then declare our needs, and only at the end we can voice our request - the specific actions we ask for. 
That’s how a nonviolent message about the problem with unwashed dishes to your imaginary apartment neighbor can sound: “According to my observations, dirty dishes have been on the table since yesterday. It saddens me and I feel very uncomfortable. I really need to live in purity and respect. Would you be willing to wash your dishes immediately after eating?”
Of course, this kind of message is not a guarantee that your neighbor will immediately change his/her behavior. It is quite possible that he/she will react aggressively even to such a polite treatment. But the basis of nonviolent communication is the belief that all people are able to empathize, so it is always worth trying to awaken it in the interlocutor.
«Giraffe language» teaches people to express themselves in a new way, to value their own feelings and needs, to connect with others, to give quality feedback. The more people in the world will just understand the concept of nonviolent communication, the more they will think about what they say and how they respond to other people's words. And there will definitely be less hate and controversy in the world.
Resources where you can find information about nonviolent communication
The use of "giraffe language" in this article is only a small part of the concept of nonviolent communication. If you are interested in this topic and want to know more, start with Marshall Rosenberg's lecture on the basics of NVC. You can watch it for free on YouTube: https://www.youtube.com/watch?v=l7TONauJGfc
If you are interested in civic activism and the civil rights movement, you can learn about nonviolence in this context from the free online course: https://www.coursera.org/learn/nonviolence?
There are also many books on the topic of nonviolent communication in various spheres of human life: Lucy Leu “Nonviolent Communication: Companion Workbook“, Liv Larsson „Human Connection at Work: How to use the principles of Nonviolent Communication in a professional way”, Dian Killian and Mark Badger “Urban Empathy”, Miki Kashtan “Reweaving Our Human Fabric” etc.