Panic is a suden fear which dominates or replaces thinking and often affects groups of people or animals. Panics typically occur in disaster situations, or violent situations (such as robbery, home invasion, a shooting rampage, etc.) which may endanger the overall health of the affected group. The word panic derives from the name of the Greek god Pan, who was said to have the ability to cause extreme, irrational fear, especially in lonely or open places. Panic is also known as Anxiety.