CrowdStrike: How an IT outage caused worldwide havoc

Flights were cancelled, trains delayed, shop tills stopped working and TV stations went off the air. All because of a faulty upgrade to a cyber security software system which triggered a global meltdown. The boss of Crowdstrike, the firm behind the system, took to social media to apologise and insisted "a fix is being put in place." But it was also a wake-up call - revealing just how quickly the ripple effect from a single glitch could affect industries across the world.