In order to determine the message that people in your dreams are sending you you must first ask yourself what that specific individual means to you. It is most likely that in your dream they symbolize the emotions that well up within you when you think about them.
Friends are a symbol of support and having fun. Whenever you dream of a friend, pay notice to your relations with that person in real life. Perhaps the dream is giving you a hint on how to resolve your problems with that person, if such exist. The dream may also be encouraging you to be a better friend, to better support the people you love.
The family is a symbol of the strong emotional ties we build with others. The father most often symbolizes authority, protection and as head of the family - leadership.
The mother is the image of caring, comfort in the home and creativity. When a woman dreams of her brother it shows her need of a man in her life, while in a man's dream he is the symbol of something unpleasant.
The sister of a woman is her need to share, and of a man - his need of a woman in his life. A grandmother and grandfather symbolize wisdom, unconditional love and traditions.
When a former sweetheart appears in your dream it means that you have still not forgotten them. This dream is showing you how to say goodbye to an old love and move on. What you need to do is pay attention to the conversation you're having with your ex.
The workplace can also be associated with family. After this sort of dream you need to once again ask yourself what kind of emotions the specific person provokes in you. Often when you dream of your boss it's a sign that you have an authoritative figure in your life that wants something. It may also be encouragement to further advance your professional skills so you don't lose your job.
People don't typically dream of random strangers but usually someone who reminds them of someone they know. After you wake up, think about whom the stranger in your dream makes you think of.