Shadow is a concept in psychology. Carl Jung made the concept famous in his work. You might want to pay attention because understanding shadows can lead to personal growth.
Shawdow is the unconscious part of your personality that does not conform to your egocentric ideal. Your ego paints a picture of what you think you are. Rigteous, moral, kind, and generous.
You can pick your own terms. Sometimes, though, this image is not complete. There are aspects of you or occasions when you may not be.
Exploring, acknowledging, and addressing your shadows, then, is a way to personal development. We all have several beliefs, schemas, and emotions that create our personalities. Many of these are formed in our journey of growing up.
Jungian psychology explains, for example, how a person could have been led to believe that being demanding and assertive is being selfish. Think of the other before yourself; she may have been taught. Such a person may repress their emotions of resentment about not getting what was fair and deserved.
It would therefore help to first acknowledge these dark emotions. There is a German word for these emotions, Hintergedanken, used by Alan Watts, the famous philosopher.
Hintergedanken is a thought in the far recesses of your mind, a thought that perhaps you might not wish to accept.
However, only by accepting it and then learning to cope with and overcome it can your personality grow. In fact, being able to be at peace with all facets of your personality, even the ones you choose to suppress, is a necessary part of growth.
Over the past ten years, I have slowly started to explore my shadows. In the beginning, I did not realise I was doing so. I was doing it more out of a desire to understand myself.
When I read the psychology and realised it was a way of growing, I did more. It requires forgiveness. Forgiveness to accept that you are what you are, flawed or otherwise.