Follow Friday, #followfriday or #ff as it is more commonly referred to as, is a Twitter trend that sees users recommend a friend or an interesting person to all of their followers.
The logic behind it is that somebody who is proud of their friends and thinks they should be seen and heard by more people can share this information with others who may have similar interests.
Likewise, if you're new to Twitter and don't have a clue who to follow, who better to advise you than one of you than one of your friends?
The concept was thought up by Micah Baldwin as he drove to work on a Friday in January 2009. Baldwin was thinking about two of his friends and how lucky he was to know the both of them. Baldwin felt that the two had so much in common that they should follow each other on Twitter. When he arrived at his destination he typed the following message (or tweet): "I am starting Follow Fridays. Every Friday, suggest a person to follow, and everyone follow him/her. Today its @fancyjeffrey & @wiredone."
Another person suggested putting a hash tag in front of the follow Friday term (having a hash tag helps to identify topics on Twitter), as the hash tag would help users to search the follow Friday posts with greater ease.
By the end of the day the craze had swept Twitter, with users from all over the world taking the time to recommend their most interesting followers. After the first day Baldwin expected #followfriday to fizzle out, but every Friday since has seen more and more people use the feature.