Facebook confirmed Wednesday that it now has 500 million users on its social networking site.
That's about 15 times as many people as in Canada, and if Facebook was a country, its population would rank behind only China and India.
Six years after getting its start in a Harvard dorm room, Facebook says it is aiming to have one billion members, matching the reach of search giant Google.
Last summer, Facebook had 250 million users and has amassed 100 million new members since February alone.
Facebook founder Mark Zuckerberg says in a blog post that he could have "never imagined all of the ways people would use Facebook."
In a video message on his Facebook page, Mr. Zuckerberg says "half a billion is a nice number but the number isn't what really matters here." He says what matters are "all of the stories we hear" from users about the impact their connections have had on their lives.
To mark the milestone, the site has launched "Facebook Stories" to highlight stories about the impact Facebook has had on people's lives.
The app, on stories.facebook.com, lets users search stories by location or by such themes as crime fighting, grief, health, politics, love and reunions.
You can "like" or share certain stories you find interesting and submit your own Facebook anecdote.