Many people in the world react to fear in many different ways but here are a few of the common ones. The First common way for someone to react would be to get all jumpy or parinoid. Another way would be that some people get very shaky. Next, some people just can't resist screaming when they get scared. Last but not least, some people get all of the above or more than one of those ways to react to fear. So that is how most people react to fear when they get scared.