Founder Mark Zuckerberg said: "We figured that rather than having this birthday that focuses on us, we should make sure that the world focus on what's important that's actually happening, which are only stories of how people are connecting around the world and it's just amazing and it's inspiring to hear."
Facebook Messenger, the site's instant messaging spin-off, has also introduced two new sets of stickers called "Best Friends" and "Friendship" that can be downloaded free and used in conversations.
Mr Zuckerberg, along with fellow Facebook executive Sheryl Sandberg were holding a Friends Day event at the company's Menlo Park headquarters, hosting Facebook users with "extraordinary" stories of friendship.
The group included GirlCrew, a Facebook group originally created in Dublin, which empowers women to find friends and organise events in their area. There are now 22,000 people in GirlCrew Facebook groups in more than 40 cities worldwide.
