The best way to show your age: What does the "#" symbol stand for?
For many, it's the pound sign. If you grew up in the age of social media, then it's the hashtag.
On Wednesday, Twitter celebrated the 10th birthday of the hashtag, first used in a tweet published on Aug. 23, 2007.
how do you feel about using # (pound) for groups. As in #barcamp [msg]?— ⌗ChrisMessina (@chrismessina) August 23, 2007
The hashtag was created to help organize tweets based on a similar topic, such as #MondayMotivation or #Hashtag10, in honor of the hashtag's anniversary.
An average of 125 million hashtags are shared every day, says Twitter. Among the most popular: #NowPlaying, tweeted more than 1 billion times, and #FollowFriday, used more than half a billion times.
As for additional popular hashtags over its Twitter lifetime:
Sports league: #NFL
Sporting event: #SuperBowl