Many, if not most, of the operations of the mind take place below the level of conscious awareness. The conscious mind contains all the thoughts, feelings, cognitions, and memories we acknowledge, while the unconscious consists of deeper mental processes that are not readily available to the conscious mind; much of human motivation and interpersonal attraction takes shape beyond conscious awareness. The unconscious is the repository of automatic skills, the source of stored memories, intuition, fantasy and dreams, and an engine of information processing.
Freud was the first to recognize the importance of the unconscious. However, his view that the unconscious mind is primarily a dark and roiling reservoir of sexual drives and improper impulses has given way to more modern understanding. It is now understood, for example, that many judgments and decisions are made "automatically," by the unconscious mind.
While it is difficult to measure what exists in the unconscious, scientists know that even fleeting perceptions—too swift to register on conscious awareness—can leave lasting imprints on the unconscious mind. Consciousness requires attention. Information can register in the absence of directed attention.