Stress can be caused by general life stressors like heat, cold, and hunger, or by more specific stresses like the sound of a barking dog. There are two main types of stress - distress/damaging stress which includes extreme emotions, and eustress which includes motivating emotions. Additional types include work stress, family stress, chronic stress, acute stress, daily hassles, trauma, and crisis. The body responds to stress through physiological changes like increased heart rate and blood pressure, and emotional responses like negative emotions such as anger and anxiety, or positive emotions such as happiness and relief.