Defense mechanisms are psychological strategies used by individuals to cope with anxiety and protect their self-esteem. They often operate unconsciously, helping people manage emotional conflicts and stress. Common examples include denial, where a person refuses to accept reality, and projection, where one attributes their own undesirable feelings to others. These mechanisms can be healthy or unhealthy, depending on how they are used. While some, like sublimation, can lead to positive outcomes by channeling negative emotions into constructive activities, others, such as regression, may hinder personal growth by reverting to earlier behaviors in times of stress.