MINNEAPOLIS (WCCO) — Thursday morning, Twitter became a publicly traded company. Stocks soared and put the value of the social-media company at more than $30 billion.

So with Twitter in the news, we wondered about one of its most well-known symbols — the hashtag.

A viewer named Valerie asked: How did the pound sign become a hashtag?

Hashtags are used on Twitter, Facebook and Instagram. The # symbol goes in front of a word or words to group that tweet or post with other tweets or posts about the same topic.

“It’s so people can find certain topics or events or things that are popular,” said teacher Stephanie Baldvin from Northfield. Common examples might be #Vikings, #NovemberSnow or #WorstPickupLinesEver

It all started back on Aug. 23, 2007 with a tweet by San Francisco techie and former Google developer Chris Messina. He wrote on Twitter, “How do you feel about using # (pound) for groups. As in #barcamp [msg]?”

how do you feel about using # (pound) for groups. As in #barcamp [msg]? — Chris Messina™ (@chrismessina) August 23, 2007

“It was one of those things where I had so many haters in the beginning that I thought this thing would never pick up,” he said in a recent interview with WCCO-TV. “But, secretly, I sort of felt like, Come on, guys, this is the simplest thing that could work.”

At first, Messina said he was dismissed by most in the tech community, including Twitter.

“People were like, that’s weird, that’s kind of dumb. You do whatever your things is, and we’ll keep complaining about the problem,” he said.

He came up with the hashtag to find an easy way to bring together people discussing the same topic online.

He chose the # symbol because it was an easy keyboard character to reach on his 2007 Nokia feature phone and other techies were already using it in other internet chat systems.

“I didn’t need to invent something new,” he said. “This is good enough. I’m going to go with this.”

Two days later, another techie, Stowe Boyd, suggested the # symbol be called a hashtag.

“It just sounds catchier,” said Messina.

Messina started using the # symbol and convinced some of his friends to do the same. During the 2007 San Diego fire, people started to use the tracking system Twitter had in place, but the spaces between the words San, Diego and fire made it difficult to track. Messina suggested the hashtag with no spaces.

“That caused other people to see that behavior and they emulated that behavior and it kind of continued in that form,” he said. “At that point, it became easier to use.”

In 2008, conservative groups began to the # symbol to encourage Congress to vote on an energy bill.

“We had culturally jumped from the tech crowd into the political space and that was huge, he said.

By 2009, Twitter adopted the idea and hyperlinked to the hashtags. Messina said that’s when its usage skyrocketed.

The # sign has become something of a cultural phenomenon. The origin of the first # (pound) sign isn’t entirely clear, but linguists think it came about because it was easier to write than L-B. The # sign became even more popular in the 1960s when Bell Labs used it on its telephones.

Now, the word is used as a verb – hashtagging – and even Jimmy Fallon and Justin Timberlake created a parody http://www.youtube.com/watch?v=57dzaMaouXA about the symbol’s overuse. For example, three or more hashtags in a tweet or post might be considered excessive.

“I hate those users,” said Ellen Stenson of California.

Messina says he’s often asked about the overuse of the symbol.

“I think there are some interesting opportunities to do a better job to help people meet, find each other, share content and get it out there in the world that aren’t just based on blowing up hashtags in your posts,” he said. “We haven’t actually found those yet and, until we do, people are going to continue to use them in that way because they are desperate to connect.”