Communication can mean a various different things. Humans communicate through our various languages, we communicate through our expressions, through our emotions, and through our actions. Through history, like animals evolve, our communication too has evolved, allowing for us to communicate like never before.
The first things that come to mind when thinking about communication may be speaking, mail, and virtual messaging. Through these, humans communicate to each other, each message for a different purpose. Perhaps you sent a postcard to your grandma to wish her a happy birthday. Perhaps a school professor speaks so that he may pass knowledge on to others, or perhaps an email was sent to inform a worried family that a loved one they had known their whole life has passed away.
While language such as words and messages are what first come to mind, these are not the only forms of communication. The actions humans take is another form of communication that can tell a lot about a person, about who they truly are. People understand if someone is bad as they communicate this by robbing a store, while the cop arresting the criminal has communicated that he is a good person by stopping the bad.
And one of the final form of communication is our emotions. Emotions can communicate a lot about a person and what their going going through. For example, a sad and depressed emotion can communicate to others that something has gone wrong in your life. A happy and excited emotion, however, can communicate to others that something in your life has gone right.
So, to answer the question of what communication, is simply the ability for others to read you. For others to understand the messages you try to convey to others, whether through your words, actions or emotions. All communication is meant to explain to others something. What makes a good communicator, then? Well, a good communicator is simply someone who can convey their ideas or thoughts through their actions, words, messages, or emotions.
Disclaimer: I didn't actually count the words in this paper, but if nothing else, I gave you a starter. Hope this helps!