There is a whole range or spectrum of lucidity... Sometimes I am lucid (aware that I'm dreaming, but feel as if I have little or no control -kinda like swimming, but in a strong current where it just sweeps you away). Other times I am completely lucid and have near total control (able to change the landscape, fly, metamorphasize into other people, animals, etc. etc. etc.). Other times I am only partially lucid but almost feel drunk or half-aware. And... sometimes I am asleep, but aware of my surroundings (usually sleep paralysis). There is a wide range, but lucid generally means you know you're dreaming while you are dreaming