These days, hashtags are known as a simple way to categorise information posted on social media.
But their inception was far from straightforward.
In Twitter’s early days, users were pleading for a way to group their tweets and streamline important information in an easy-to-find category.
Then, on 23 August, 2007, social media changed forever, thanks to a man named Chris Messina.
After gauging responses to his ideas on his blog, Messina began studying tags on image hosting site Flickr and understanding the grouping functionality.
He then began proposing the using the "pound" or "hash" symbol as an indicator of these tags.
And although the hashtags were initially intended to be used as metadata (to provide additional data about a tweet), a significant event caused them to take on a life of their own.
The first hashtag
In one of his August proposals, Messina tweeted the first recorded hashtag: #barcamp.
This "test" tag referred to an international network of user-generated technological and web-based conferences.
The hashtag idea did not initially catch on, but that all changed in October that year, when wildfires tore through southern California, destroying homes and burning millions of acres of land.
Messina noticed San Diego resident Nate Ritter, a friend from BarCamp, reporting news of the fires on Twitter.
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He reached out to Ritter and encouraged him to use #sandiegowildfire in his tweets to help them reach a wider audience.
Ritter did so, and soon other Twitter users began using #sandiegowildfire too and tracking the hashtag for updates about the fires.
Not all #smoothsailing
Getting users to accept hashtags wasn’t an easy process.
Twitter co-founder Evan Williams reportedly told Messina that hashtags were "too nerdy" to go mainstream.
Twitter users were also unhappy with their appearance, criticising the lack of spacing and the appearance of the "hash" symbol for looking messy.
But as the social network grew, so did the need for hashtags. Twitter came around to the idea and users began to see its value.
There are now about 328 million users on Twitter, sharing more than 125 million hashtags per day.
Twitter now refers to 23 August as #HashtagDay and is this year commemorating it by launching a special emoji in several languages.
"In the first half of this year, a whopping 12.6 billion tweets globally included at least one hashtag, proving that people on Twitter are continuing to use the hashtag in creative ways," a spokesperson said.
Other social networks also use the feature, and Twitter is continually trying to stay ahead of the game by implementing new features.
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