I communicate with someone to get my point across, this is my main aim in conversations other than just pointing out simple comments.
Conversations with a group of people to maybe only one or two can be hard if you don't now what to say or your don't have a point decided in your mind before the conversation has already taken place. Conversations help you to get to know the other person; their character and see what topics they see of interest compared to your own.
Having a conversation with someone can also be a stress reliever, when you have something on your mind that would be easier to communication with someone else and make the load easier for you to handle.
Before you start a conversation always know what your about to say - perhaps discuss or say what you would say in your mind and try to interpret what the other persons reaction would be, this wont make you look stupid at the end of the day or your conversation pointless.