Final answer:
PTSD is an anxiety disorder that occurs after experiencing severe psychological trauma. Factors such as genetics, previous trauma, and individual coping mechanisms can contribute to the development or resilience to PTSD.
Step-by-step explanation:
Post-traumatic stress disorder (PTSD) is an anxiety disorder that occurs after experiencing severe psychological trauma. It is caused by exposure to traumatic events such as military combat, physical assaults, terrorist attacks, and natural disasters. Not everyone who experiences traumatic events develops PTSD. Factors such as genetics, previous trauma, and individual coping mechanisms can contribute to the development or resilience to PTSD.