Lucid dreaming is dreaming while knowing that you are dreaming. The term was coined by Frederik van Eeden using the word "lucid" in the sense of mental clarity. Lucidity usually begins in the midst of a dream, when the dreamer realizes that the experience is not occurring in physical reality, but is a dream. Often this realization is triggered by the dreamer noticing some impossible or unlikely occurrence in the dream, such as meeting a person who is dead, or flying with or without wings. Sometimes people become lucid without noticing any particular clue in the dream; they just suddenly realize they are in a dream. A minority of lucid dreams (according to the research of LaBerge and colleagues, about 10 percent) are the result of returning to REM sleep directly from an awakening with unbroken reflective consciousness.
The basic definition of lucid dreaming requires nothing more than becoming aware that you are dreaming. However, the quality of lucidity varies greatly. When lucidity is at a high level, you are aware that everything experienced in the dream is occurring in your mind, that there is no real danger, and that you are asleep in bed and will awaken shortly. With low-level lucidity you may be aware to a certain extent that you are dreaming, perhaps enough to fly, or alter what you are doing, but not enough to realize that the people are dream representations, or that you can suffer no physical damage, or that you are actually in bed.
Lucidity and control in dreams are not the same thing. It is possible to be lucid and have little control over dream content, and conversely, to have a great deal of control without being explicitly aware that you are dreaming. Nonetheless, becoming lucid in a dream is likely to increase your deliberate influence over the course of events. Once you know you are dreaming, you are likely to choose some activity that is only possible in dreams. You always have the choice of how much control you want to exert, and what kind. For example, you could continue with whatever you were doing when you became lucid, with the added knowledge that you are dreaming. Or you could try to change everything--the dream scene, yourself, other dream characters, etc. It is not always possible to perform "magic" in dreams, like changing one object into another or transforming scenes. A dreamer's ability to succeed at this seems to depend a lot on the dreamer's confidence. If you believe that you cannot do something in a dream, you will probably not be able to.
On the other hand, the easiest (and perhaps wisest) kind of control to exert in a dream is control over your own behavior. This comes in especially handy in nightmares. If you become lucid in a bad dream, you could try to do magic to escape the situation, but many times this does not work very well. It is generally much more effective, and better for you psychologically, to recognize that, because you are dreaming, nothing can harm you. Your fear is real, but the danger is not. Changing attitude in this way usually defuses the dream situation and transforms it into something positive
