knowledge and understanding

Knowledge and Understanding is a total different thing.
When your mother gave you a 50 lists of things for you to do, thatz knowledge, but when experince doing smthing, thatz called understanding.

Why people has no urgency about their health? For example, most of the people knows that smoking is not just good for their on health but also for the ones they love, but some dont even care to consider to stop doing it. This is called knowledge. But then when some close people or family friends died because of it, they will click and start to consider. And this is called Understanding.