By different backgrounds, I understand cultural context that defines how a person act: habits, code of appropriate behavior, values, norms etc. Am I right? If so, the thing is that people with different cultural background may have troubles understanding each other. To make the question a little easier to discuss let’s divide different ways of communication. I suggest outlining verbal and nonverbal ways of communication that, and I should say it right away, rarely can be considered completely separately. Instead, they complement each other. But it’ll be easier from the methodological perspective.
So verbal communication is a basic type of transmitting your opinion (question, command etc) to another person - by words. I’d leave aside the situations when you need to understand each other with a person who speaks some other language. I consider only a case when you talk the same language but have a different background with your interlocutor.
Depending on the purpose of your communication you should pay attention to:
What I want to say is that communication is a complex process that requires not only knowing basic rules but some kind of intuition. And when you are trying to come to a mutual understanding with a person with another background, you should be more attentive and thoughtful about your way of saying things.