Complexes
Early in Jung's career he coined the term and described the concept of the "complex". Jung claims to have discovered the concept during his free association and galvanic skin response experiments. Freud obviously took up this concept in his Oedipus complex amongst others. Jung seemed to see complexes as quite autonomous parts of psychological life. It is almost as if Jung were describing separate personalities within what is considered a single individual, but to equate Jung's use of complexes with something along the lines of multiple personality disorder would be a step out of bounds.
Jung saw an archetype as always being the central organizing structure of a complex. For instance, in a "negative mother complex," the archetype of the "negative mother" would be seen to be central to the identity of that complex. This is to say, our psychological lives are patterned on common human experiences. Interestingly, Jung saw the Ego (which Freud wrote about in German literally as the "I", one's conscious experience of oneself) as a complex. If the "I" is a complex, what might be the archetype that structures it? Jung, and many Jungians, might say "the hero," one who separates from the community to ultimately carry the community further.
Read more about this topic: Analytical Psychology