Identify different reasons why people communicate?

Humans communicate for a wide variety of reasons. Put simply, our survival and success has been dependant on our ability to communicate. With good communication and teamwork, animals are able to avoid predators, as well as kill other animals far bigger than themselves. That shows why we've evolved to have great communication from an evolutionary perspective, and why we communicated in the first place.

Communication still plays a vital part in our survival, for example a baby will scream (which is a form of communication), when it is hungry. Also sharing ideas though communication has meant that each generation of humans has been able to refine and improve the previous generations work. There is simply no way that something as complex as an engine could have been designed by one person. It took years of thinking and ideas communicated down generations before the engine could finally be a reality.

Socially, communication is very important. We want to make friends with people who will listen to our ideas, and also to keep in contact with those who are close to us (family etc). Talking is often about letting someone else understand your point of view, or about finding common ground between two (or more) differing opinions. Communication satisfies our constant need to relate to others, and have them relate to us.

Lastly, communication forms the basis of a strong relationship between two people. Its way for us to find a suitable partner, and communication allows us to achieve intimacy. Remember that communication encompasses not just talking (verbal communication), but also body language and other forms of non verbal communication.

Identify the different reasons people communicate?

Explain how effective communication affects all aspects of own work

Communication is the necessity of every human being and is the basis of formation of successful human societies. Without communication It won't be possible to human societies to develop or even exist. Humans are dependent on each others skills to fulfill their different necessities either it is socialization, having family, getting their needs fulfilled by others or to be recognized. It is the communication between humans that their problems gets recognized and solution to those problems are devised. It is need of communication between humans that makes them above from all creatures and make them call social animal.
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What Allows People To Communicate Their Ideas?

Because they want to share different information or to keep contact with them who they are communicating.

For many reasons including simple survival - we need to exchange information necessary to our survival - and also our most basic sexual and social needs. Humans are made to communicate and don't thrive if they aren't exchanging ideas, news or just social noises with each other.

The answer depends on what the question is asking exactly.  What drives humans to communicate or what is the purpose of humans communicating with each other?  If the drive is the question, I would say humans ultimately want to be happy, so whatever makes them happy is what drives them to communicate.  For example, if recognition by others is one of the things that makes you happy, you'll sneak in telling others about your achievements.  If the question is about the purpose, then the answer above applies.