Emotions, often called feelings, include experiences such as love, hate, anger, trust, joy, panic, fear, and grief. Emotions are related to, but different from, mood. Emotions are specific reactions to a particular event that are usually of fairly short duration. Mood is a more general feeling such as happiness, sadness, frustration, contentment, or anxiety that lasts for a long period.
Although everyone experiences emotions, scientists do not all agree on what emotions are or how they should be measured or studied. Emotions are complex and have both physical and mental components.