Follower
A term used to describe a person who is following another person on the social networking site Twitter. Every Twitter profile page has "Following xxx", where xxx is the number of people that person is following and "Followers xxx", where xxx is the number of people that are following that person.
When following someone on Twitter each post that person makes will be posted on your Timeline. Users who are more familiar with Facebook can think of a follower as a Friend. However, when following someone on Twitter it will not require them to accept, unless their Twitter page is private.
Finally, if you want to stop following someone, you would unfollow that person.
Also see: Friend, Internet definitions, Twitter