Facebook and Facebook Messenger went under for users all over the world tonight.
Others have reported problems with Instagram as well.
The outage lasted less than 10 minutes for some, but others are still reporting problems.
It seems that some people are getting the social media apps back faster than others.
Thousands attended the Down detector Website to comment.
Facebook warned users that an unknown error had occurred.
People from all over the world said it was all down, from Australia to New York.
Facebook has not yet commented on the issues, but it has had similar issues in the past with all of these services failing at the same time.
It last happened on March 19, when WhatsApp, Facebook and Instagram went down.
Thousands around the world were affected.
Instagram and WhatsApp are both owned by Facebook.