Definition.
The ego is the part of our psyche that we experience as ‘I,’ which experiences conscious awareness. Freud distinguished the ego from the id and superego, but Jung simply considers the ego, or ego-complex, to be one complex among many.
Still, the ego-complex does differ from other complexes in a few important ways. First, it is outward-facing — it does its work primarily in the outer, waking world. Second, it is understood as being conscious, while other complexes have their origin in the unconscious. Additionally, the ego is responsible for tasks which are braided with consciousness, such as negotiating material reality through thinking and applied will. The application of ethical considerations to lived experience is also a responsibility of the ego.
The ego is not, in any way, bad. To have an ego is not to be egotistical. The main trouble with the ego is that it tends to believe that it, alone, represents the interests of the psyche. It feels itself to be the sole figure and ‘decider’ in the inner world, rather than a member of a wider community peopled with many other complexes. On this basis, part of the individuation journey involves the relativizing of the ego — the discovery that ego exists in relation to inner-others who have their own distinct perspectives.