What is a Follower on Social Media?
A follower is a user in a social media website that "follows" another user, meaning they receive notifications through their feed when the followed user posts a new post. Consequently, when a user posts something, their post is sent to the feeds of all their followers. The more followers you have, the larger your audience that will be notified when you post something new.
In some platforms, like Youtube, the term "subscribe" is used instead of "follow," thus the term "follower" becomes "subscriber."