Defense mechanisms are "unconscious" strategies employed by the ego to reduce anxiety and avoid conflict.
Defense mechanisms refers to the psychological strategies that are unconsciously used to shield an individual from uneasiness emerging from inadmissible considerations or sentiments.
We use resistance systems to shield ourselves from sentiments of tension or blame, which emerge on the grounds that we feel undermined, or in light of the fact that our id or superego turns out to be excessively requesting. They are not under our cognizant control, and are non-voluntaristic.