Communication - a fairly long word, a complex subject to discuss, and a hard term to define. But allow me to take a "leap of faith" and offer two definitions for your consideration (and, hopefully, comment).
Communication is first of all about interpretations. Nothing comes to us with its meaning inscribed on its back. What something means to you or to me is always in interpretation. As you read this, you are interpreting what I have written. As I wrote it, I was interpreting a lifetime of thinking about communication, of studying it, of researching it. Beyond that, I was faced with how best to package my interpretations so that your interpretations could possibly be of optimal value to you. No mean trick.
Consider that if you and I are to "communicate," each of us has to reach across the chasm that separates us to consider how to deal with the interpretations you might make of what I write.
Communication is also the process that creates (and maintains or changes) the minds we have. And our minds are the sources of all of our ways of "minding" the world - all of our ways of seeing it and dealing with it, and all of our ways of being affected by it and by each other. That process is not self-correcting. By and large, we go where our minds lead us, where and what they make possible - and necessary. It is our minds that control what we see and feel, not us.
Everything of which we are conscious got there via communication with others or with ourselves.