Divination includes a wide range of different magickal practices and overlaps quite a lot with the practices of astral travel and pathworking. Essentially divination is any practice which allows the practitioner to be allowed a deeper insight into things as they are or as they are likely to be. It includes such things as Tarot divination, I Ching, divination by Runes, Geomancy and Clairvoyance.
Divination differs from simple "fortune telling" in that it does not seek to inform the practitioner of what will happen, rather it gives insights into particular aspects of the question, allowing the querent (the person for whom the divination is being done) to follow various streams of thought and arrive with a greater understanding of the situation and of themselves and how the two interrelate. The purpose is often to try to get an understanding of what things are important to the situation and thereby make a more informed decision as to the best course of action to take. Sometimes this insight comes as a vision or a deep conviction which seems unrelated to the method of divination that is being used.