The word "emotion" dates back to 1579, when it was adapted from the French word émouvoir, which means "to stir up".
Emotions have been described as discrete and consistent responses to internal or external events which have a particular significance for the organism.
Emotions are brief in duration and consist of a coordinated set of responses, which may include verbal, physiological, behavioural, and neural mechanisms.
Feelings are best understood as a subjective representation of emotions, private to the individual experiencing them.
Moods are diffuse affective states that generally last for much longer durations than emotions and are also usually less intense than emotions.