New York - Facebook is updating its status to "public company" as its stock jumps in its debut on the Nasdaq Stock Market.
The stock rose to $42.05 on Friday morning. CEO Mark Zuckerberg smiled as he rang the opening bell from Facebook's headquarters in Menlo Park, California.
Surrounded by cheering Facebook employees and wearing his signature hoodie, the 28-year-old pushed the button that signals the opening of the stock market in New York.
On Thursday, Facebook and the investment bankers arranging the IPO settled on a price of $38 per share.
The company and its early investors raised $16bn in the offering, which valued Facebook at $104bn. That makes Facebook the most valuable US company to ever go public.
Now, the stock market will assign a dollar value to Facebook that will rise and fall with investor whims. It will be subject to broad economic forces as well as how much profit it earns from one quarter to the next.
But Facebook is one of the rare companies whose IPO transcends Wall Street's money lust to become a cultural touchstone for the way technology is reshaping our lives.
Since its start as a scrappy network for college students, Facebook has come to define social networking by getting 900 million people around the world to share everything from photos of their pets to their deepest thoughts.
It has done so while managing to become one of the few profitable internet companies to go public recently. It had net income of $205m in the first three months of 2012, on revenue of $1.06bn.
In all of 2011, it earned $1bn, up from $606m a year earlier. That's a far cry from 2007, when it posted a net loss of $138m and revenue of $153m.
The company makes most of its money from advertising. It also takes a cut from the money people spend on virtual items in Facebook games such as FarmVille.
Facebook's public debut marks a new milestone in the history of the internet - and the people who use it.
In 1995, Netscape Communications' IPO gave people their first chance to invest in a company whose graphical web browser made the Internet more engaging and easier to navigate.
Its hotly anticipated IPO lit the fuse that ignited the dot-com boom and culminated five years later in a devastating bust that obliterated the notion that the internet had somehow hatched a new economy where making money no longer mattered.
It took Google's IPO in 2004 to prove just how profitable a well-run internet company with a disruptive idea can be.
In the process, the internet search leader is forcing other industries to adapt to a new order where people have come to expect to be able to find just about anything they want by entering a few words into a box on any device with an internet connection.
Facebook's IPO underscores an internet evolution that has made the understanding of connections among people as important as Google's massive index of Web links.
Now that Facebook will be under greater pressure to sell more advertising to bring in more revenue, this IPO also cast a brighter light on how just how much revealing information that people have been sharing the past few years without fully understanding the implications.
Facebook's IPO almost certainly will enrich other up-and-coming entrepreneurs as Zuckerberg uses the company's trove of cash and stock to buy other startups in an effort to being in other talented engineers and promising technology.
That's what has been doing for years. Since it went public in 2004, Google has spent $10.2bn buying nearly 200 other companies.
Those figures don't include Google's still-pending $12.5bn acquisition of cellphone maker Motorola Mobility Holdings, which is still awaiting regulatory approval in China.
Zuckerberg's biggest deal came so far when he agreed to buy Instagram, a maker of a popular mobile app for photos, for $1bn. Because most of the deal is being paid for in stock, Instagram is already getting richer.
Based on Facebook's IPO price of $38 per share, Instagram is in line to receive nearly $1.2bn.
Though Zuckerberg rang the Nasdaq opening bell from California, people outside the stock market in Times Square snapped photos of a big blue Facebook sign that lit up the building.
Some of them used their smartphones to checked in to the Nasdaq on Facebook. Frederick Nolde, who was visiting from Richmond, Virginia, said he bought 100 shares through the online brokerage eTrade.
He thinks the company is worth $100bn. "I think Google is a good comparison and it's worth $20bn0 to 300bn.
"The real question is how they do in mobile. If they can figure that out they'll do well."