This Twitter user 'invented' the hashtag in 2007 — but the company thought it was 'too nerdy'
Today, the hashtag is ubiquitous on platforms like Twitter and Instagram as well as Facebook, Snapchat and TikTok. Log on to Twitter anytime and you'll find a list of trending hashtags with tens of thousands of tweets apiece. But the hashtag hasn't always been a social media tool. Someone had to dream of using it that way — and convince Twitter that the idea wasn't "too nerdy." That someone was Chris Messina, who in 2007, had an idea he thought could make then newly launched Twitter easier to use: Put a pound symbol in front of words or phrases in tweets in order to filter them by topic and maybe even make them searchable. While it's impossible to estimate the number of hashtags on social media today, if Messina received a penny for every time someone posted on Instagram with the hashtag "#love" alone (one of the web's most popular tags and with over 1.7 billion Instagram posts), he would have $17 million and counting. Alas, Messina, now 38, did not monetize his idea, but it did change social media history.

The problem with early Twitter

In 2007, Twitter was a year old and Chris Messina was a tech product designer running his own internet consulting company. Messina and his Silicon Valley friends were using Twitter, but found the endless, unorganized scroll of tweets made it next to impossible to isolate groups of messages around a certain topic.

A screengrab of Twitter's homepage circa 2007. Source: Twitter/Web Design Museum

Messina thought if people used the same word or phrase and put the hash symbol in front of it that could "create an instant channel that anybody can join and participate in" in the conversation, Messina tells CNBC Make It. That was the "genesis of the idea," Messina says. He picked the pound sign as a nod to the chat platform Internet Relay Chat (IRC) that he and many of his friends in tech used to communicate at the time. IRC featured various channels, where users chatted about relevant topics (similar to newer platforms like Slack, Messina says) and the channel names were also preceded by a pound symbol. Messina set out to see if he could get other Twitter users on board with his hashtag idea. In August 2007, he tweeted a question to his followers asking how they felt about using the pound symbol to make it easier to follow conversations about specific topics. More than a decade later, that somewhat prophetic tweet has more than 10,000 "likes" and nearly 5,000 retweets, but Messina tells CNBC the post mostly received "mixed reviews" at the time. (The tweet references BarCamp, a series of tech workshops that Messina helped create.) 2007TWEET "So, I started to kind of experiment and put down symbols in front of words and places that I was going to, you know, just kind of trying to get the ball off the ground," says Messina.

It's too nerdy

Of course, at that point, putting a hashtag in front of a word or phrase in a Twitter post did not automatically create a channel or link to anything. So Messina wrote a 2,000-word proposal for his hashtag idea — including mock ups of how he envisioned the hashtagged channels would look — and he took it to Twitter's headquarters in San Francisco. "I walked in the front door, because they didn't have security, and I walked up to Biz Stone, one of the co-founders and, kind of, presented my idea," Messina tells CNBC Make It.

Chris Messina, creator of the hashtag, in 2005. Source: Chris Messina/Flickr

Stone (who subsequently left and then returned to the company in an unspecified role in 2017) wrote in a Medium post that Messina walked into Twitter's "grungy office" and pitched the hashtag idea to Stone and a few other Twitter employees while they "were working frantically to fix a tech issue that had brought Twitter down, as was often the case in those early days." Messina says that the preoccupied Stone "probably half-listened to my idea and then kind of dismissed it out of hand as being something that was too nerdy that would never catch on." Messina says Stone also promised that Twitter could simply write an algorithm to solve the problem of sorting topics of discussion.

Twitter offices at 164 South Park in San Francisco, California in March 2008. Courtesy of Biz Stone

Twitter users make it happen

As it happened though, Messina's hashtag idea ended up taking off anyway. Messina kept promoting hashtags through his own social media accounts and in conversations with friends. Then that October, Messina convinced a friend named Nate Ritter to use hashtags in his tweets posting information about a San Diego wildfire, and pretty soon other Twitter users were following suit in order to keep track of tweets sharing news about the wildfire. The event ended up being an "important test case" for Messina's idea, he says, and Wired even wrote an article about the phenomenon that helped create more awareness of how hashtags could be used on Twitter. From there, Messina convinced some third-party developers who were building apps for Twitter users to add support for hashtags to their apps. (One of those third-party apps was Summize, a content summary app that Twitter eventually acquired for a reported $15 million in 2008.) As more people started using hashtags, and more developers were building apps for Twitter that recognized the hashtag, Twitter eventually got on board with the idea. In 2009, the company added an automatic search tool that allowed users to search the platform based on a specific hashtag. From there, use of the hashtag spread beyond Twitter to other platforms, including Instagram, which launched in 2010.

It's a hashtag world and Messina is just living in it