Technology blackouts: Why did Facebook, WhatsApp and Instagram stop working?

Social media platforms Facebook, WhatsApp and Instagram are back up and running after a six hour outage.

Facebook said the blackout had been caused by an internal technical issue, which not only affected Facebook's services, but reportedly also employees' work passes and email.

More than 3.5 billion people worldwide use Facebook, Messenger, Instagram and WhatsApp.

An outage of this size for such a long time is a rare event. But here are five other times technology fails have caused major disruption.

What did you think about the Facebook, WhatsApp and Instagram outage? Tell us your thoughts in the comments section below.

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