Down Detector has provided an overview of the unavailability, where it has confirmed that the outage currently affects a huge number of those who happen to live in the UK, as well as the rest of western Europe. Not only that, the lack of functionality has also spread all the way across the Atlantic to the US east coast, while there are some patches of unavailability over in the west coast to boot.
It is with some irony that the hashtag #facebookdown happens to be trending on Twitter at the moment, as this shows all of the built-up frustration with the downtime on Facebook. Facebook has yet to step forward to share as to what the issue is pertaining to this outage. This is definitely not the first time that Facebook has experienced an outage, and you can be pretty sure that it will not be the last, either.