What Is Cascading Faults?

The idea was based that everything from your traffic lights to like mri machines have these chips embedded in them. It wasn't clear at the time, sort of what it would take to fix it, because you don't even really know what the problem is. And so another one phrases that went around at the time with this idea of cascading faults. If one of these systems breaks, will all these other systems are dependent on that one system.