Human's expression Through Emotion.

 Human is a complicated creature featured with outer physical appearance and filled with thousands emotions. some of those emotions are expressed through physiological functions such as facial expression, faster heartbeat, following behaviours such as aggression, covering face with hands even crying. each individual show their emotions with all different ways, some people show their emotion confidently and obvious, some are too shy to expressed their emotions therefore choosing to hiding it.
 in my opinion both different ways of emotion expression are depend on the individual background whether that person is a introvert they will more likely hiding their feeling and in the other hand the extrovert one choosing to share what they truly feel to others.
in the modern era like this present day people have new ways to expressed their feeling since they discovered the social medias. Now we can see easily all different patterns of these emotions. The social medias developed with space to shares pictures,videos and write a status about your thoughts and passions.
the era of social media indirectly also changed the individual ways to show their emotions. in the past we only detected the difference of the introvert and the extrovert literally by just looking at their attitudes, but now the game is slightly changed. We have the new species of the individual way of express their emotion that is the introvert who is very good at showing  their emotions through social media. this case happened often to the teenager, usually because they have low self esteem to express it directly in person but then find social media is more reliable to share their emotions. there also case when the introvert is actually want to experience more open social life by pretending to another person in the social media so they make a new circle of friends who actually people they actually never met in person so they feel  more comfortable by virtual way to express their expression because the audience are people who have no idea about their background so they feel less pressured. there also once happened in my high school a girl who is very quiet and very shy in person but she is a completely different person from her social media account from the pictures she posted showed a whole different personality, in all pictures she seems very confident and cheerful.
from the cases defined above we conclude that human emotions is unlimited mystery that probably become more complicated as it changes over times. despite that is the privileges of human feeling which is make us different from the other creatures and animals. human emotions are just and unpredictable and always developed in so many unbelievable ways.