Monday will be remembered as a landmark day for Facebook, a billion active users on the social network in just a single day.
Founder Mark Zuckerberg felt the achievement was an "important milestone", saying in a post he is proud of what Facebook has achieved so far.
On Monday, 1 in 7 people on Earth used Facebook to connect with their friends and family.
When we talk about our financials, we use average numbers, but this is different. This was the first time we reached this milestone, and it's just the beginning of connecting the whole world.
I'm so proud of our community for the progress we've made. Our community stands for giving every person a voice, for promoting understanding and for including everyone in the opportunities of our modern world.
Facebook is already looking to further expand its role in the world, announcing it's personal assistant 'M'.
The company released its normal average monthly user count just last month at 1.49 billion users, 13 per cent higher than the same period a year 2014.