The Emotions

The Emotions are main characters of the 2015 Disney/Pixar film, Inside Out. The Emotions are in charge of running the mind of the person/animal they inhabit.

There are five emotions in total: Joy, Sadness, Anger, Fear, and Disgust.

Formation & Leadership
Each Emotion is created at a different moment, usually early in someone's life. They seem to appear from nowhere.

Each person has a central Emotion that acts as the unofficial leader of the group. The central Emotion is usually positioned in the center of the group, and controls most of the person's actions. In Riley Anderson's mind, Joy is in charge, while her father's mind is controlled by Anger, and her mother's mind is run by Sadness.

The film suggests that the first Emotion to appear is the one who is in charge as Joy appears first in Riley's mind.

Residence
The Emotions reside in the mind of each person and they live and work in Emotions' Headquarters,

Appearance
The Emotions tend to take on the appearance of the person they reside in. For example Mr. Anderson's Emotions all have a mustache like he does, and Mrs. Anderson's Emotions all have their hair in a ponytail and wear thick red glasses. Various other character' Emotions resemble them in some form, like having dyed hair or multiple piercings. Riley is the only character to have Emotions that do not resemble her. This may have been done to have her emotions stand out from the rest that are seen in the film.

The look of each emotion is also based on other things. Joy is based on a star, Anger is based on a firebrick, Disgust is based on broccoli, Fear a raw nerve, and Sadness a teardrop.

Trivia

 * While most people's Emotions tend to be the same gender as they are (for example, all of Mr. Anderson's Emotions are male), Riley and some other children and teens seem to have Emotions that are mixed, having both male and female Emotions.
 * Animals are shown to have the same five emotions as humans