Emotions are the ability to express our feelings. How tense those feelings are - how much they vary, the variations between people.
Experience: Self-reported feelings
Behavior: facial expressions
Physiology:

The experiment they took was recording down Jenny’s idea and
Emotional experience is how we (subjectively) feel Often measured using self-report scales (Likert scales)


Note that emotions are studied together here. It’s not that one emotion is better than another, but it depends on what researchers like more.
Facial Action Coding System(FACS) - a specific encoding scheme that will get unique coding. (Paul Ekman)
