The id comprises the unorganized part of the personality structure that contains the basic drives. The id acts as according to the "pleasure principle", seeking to avoid pain or unpleasure aroused by increases in instinctual tension.
The id is unconscious by definition. In Freud's formulation,
“ It is the dark, inaccessible part of our personality, what little we know of it we have learnt from our study of the dream-work and of the construction of neurotic symptoms, and most of this is of a negative character and can be described only as a contrast to the ego. We all approach the id with analogies: we call it a chaos, a cauldron full of seething excitations... It is filled with energy reaching it from the instincts, but it has no organisation, produces no collective will, but only a striving to bring about the satisfaction of the instinctual needs subject to the observance of the pleasure principle.
Developmentally, the id is anterior to the ego; i.e. the psychic apparatus begins, at birth, as an undifferentiated id, part of which then develops into a structured ego. Thus, the id:
“ contains everything that is inherited, that is present at birth, is laid down in the constitution -- above all, therefore, the instincts, which originate from the somatic organisation, and which find a first psychical expression here (in the id) in forms unknown to us" . ”
The mind of a newborn child is regarded as completely "id-ridden", in the sense that it is a mass of instinctive drives and impulses, and needs immediate satisfaction. This view equates a newborn child with an id-ridden individual—often humorously—with this analogy: an alimentary tract with no sense of responsibility at either end.
The id is responsible for our basic drives such as food, water, sex, and basic impulses. It is amoral and selfish, ruled by the pleasure–pain principle; it is without a sense of time, completely illogical, primarily sexual, infantile in its emotional development, and is not able to take "no" for an answer. It is regarded as the reservoir of the libido or "instinctive drive to create".
Freud divided the id's drives and instincts into two categories: life and death instincts—the latter not so usually regarded because Freud thought of it later in his lifetime. Life instincts (Eros) are those that are crucial to pleasurable survival, such as eating and copulation. Death instincts, (Thanatos) as stated by Freud, is our unconscious wish to die, as death puts an end to the everyday struggles for happiness and survival. Freud noticed the death instinct in our desire for peace and attempts to escape reality through fiction, media, and drugs. It also indirectly represents itself through aggression.
Sorry...couldn't resist.... :P