Defenses are psychological operations that maintain equilibrium when a person cannot manage emotions that stem from conflict or trauma.
Defenses are something we ALL employ in our lives and can be divided into two categories.
"Adaptive defenses" which lead to smooth psychosocial functioning
"Maladaptive defenses" which lead to psychosocial troubles.
Defenses are largely unconscious, although insight into one's defensive structure can be obtained with psychoanalysis.
Defense mechanisms are amazing and should be regarded as exceptional feats by the psyche. I believe that analyzing defenses helps bring light to one's life and greater understanding of a person's uniqueness. Learning why certain kinds of defenses operate makes room for new adaptive defenses to grow.