Translated from Latin, the word "emotion" means "shock" or "excite", that is, this is a process in which a person is not calm: evaluating something, he somehow experiences it.
The state of experiencing emotion encompasses the whole person: various organic reactions are triggered inside, facial expressions, gaze, voice, body position, and behavior change outside. This idea is highly discussed in the papers at https://blablawriting.com/essay-examples/emotions written by students.
For example, someone stepped on your foot and didn't even apologize. At this moment, a thousand different thoughts rush through my head: “How painful! My shoes dirty now! What an insolent man! He could have apologized! If you assessed what happened as infringing on your personal dignity, then in response you can either be offended or become irritated, keep silent or go into a verbal (and maybe physical) attack on the offender. How many people so many and reactions that depend on the nature of each of them.