Last Wednesday, Facebook, Instagram, and WhatsApp were down for many users around the globe. It turned out to be the longest outage they ever had. As a Twitter user, I saw many people complaining on that platform. In fact, we saw a few people had even just signed up for Twitter so they could complain about Facebook or Instagram.
Facebook even took to Twitter to let people know what was going on. At 1:49 pm, they acknowledged they were having problems. At 3:03 pm, they confirmed that it was not a DDoS attack. On Thursday afternoon, they said the problems was due to a server configuration change that caused the problem.
Many people took to complaining on some sites that report outages, sometimes even showing a map so you can see how widespread the problem is.
You can check which sites are down at these places: