Internet has changed everything.
How it was before . . .
Picture your students going off to school. They each carry a lot of books, "stuff/data", in their backpacks. They take different routes to school - some walk, some ride the bus, some take the subway, some are driven by someone. In this "physical" world, students know a lot about safety because the can "see". They know who is safe to talk to -- the bus driver, a neighbor, a storekeeper along the way.
How it is now . . .
Online, we no longer have the cues from the physical world to help us. We can't "see". In this world of anonymity, we have an "online data persona" that is almost as real as our physical person. But we don't know where our data is, who is using it or what their intentions are. We don't know who "they" are.