Are you sure you don't mean your 'conscious' and 'sub-conscious'?
If so, your conscious is the part of your mind that is awake and actively thinking. It's the only part of the brain that most people use during waking hours. It's the part that helps you speak, hear, see, taste, touch, smell, process information, write, move, walk, do math, hold hands, kiss etc etc.
The sub-conscious is the dormant, and much more powerful and potent part of the mind. To do with old memories, fears, animal traits, instinct, bodily functions (mostly chemical regulations). It's also the part of the brain responsible for your dreams. The sub-conscious brain is very poorly understood, but it is believed to house enormous power. A lot of scientific experiments have been done on the sub-conscious. To do with hypnosis and mind-over-matter, amongst other things.
One study that wasdone found that the subconscious actually has the power to cause physical changes in the body. For instance, a person having a delusion might be convinced that they are being stung by nettles, and the mind actually will actually cause the skin to break out in little lumps.
Very interesting stuff.