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The world was also introduced to the Twitter hashtag, and it hasn't looked back.
According to Twitter, an average of 125 million hashtags are now shared daily, marking a massive jump in use.
In 2007, the most tweeted hashtag was used about 9,000 times, whereas the top hashtag of 2017 has been used over 300 million times, the company said.
Among the most common hashtags are #NowPlaying, which is often used for songs and has accumulated more than 1 billion tweets since it debuted in 2007, #FollowFriday, which started in 2009 and has been used more than half a billion times, and #ThrowbackThursday (including its shorter iteration #tbt), which has been tweeted 120 million times, according to Twitter.
The hashtag itself, which used to be known as the "pound sign" -- according to Luddites -- was invented by Chris Messina, a former Google designer.
He suggested that Twitter users could use "# (pound) for groups."
In a post on Quora in 2013, Messina said that there were two reasons why he didn't patent the idea, writing that "claiming a government-granted monopoly on the use of hashtags would have likely inhibited their adoption, which was the antithesis of what I was hoping for."
He continued, "I had no interest in making money (directly) off hashtags. They are born of the Internet, and should be owned by no one."
And for that, we are surely #blessed.