There are three main types of dreams in Dream Yoga.
Karmic/Ordinary dreams: These are the ones that basically mimic the actions of your daily life. Any thoughts, worries, problems, happenings, ect. are jumbled together in the dream. Sometimes, they Yogis believe, you even have issues from previous lives pop up in these dreams.
The exercise for sweeping out daily thoughts is meant to help minimize these dreams so you can make way for more vivid dreams.
Clear Light dreams: Although these are not lucid, they're usually the dreams that stick out in your mind as being important, vivid and spiritual. The Yogis considered these openings of energy centers, blessings from spirits/gods, or visions.
Lucid dreams: Hopefully everyone already knows what they are by now.

Within these three are six more sub-types:
• Dreams of everyday thoughts and happenings from the previous day(s)
• Dreams about other people
• Parts of the subconscious making themselves known
• Symbolic dreams, think Freud/Jungian Archetypes
• Dreams of the future, visions and the like
• Vivid, spiritual dreams
How many of each dream type have you had each night? Which dreams are the most common for you? The least common?