How to fall safely?

This is a question I’ve had for the longest time and maybe someone could clear it up for me.How does one fall safely? I’ve been taught to fall forward on your knees, but it’s still very painful?? I don’t see how that is falling safely.Also, how do you fall backwards? Usually when I fall, it’s unexpected so how I cant bring myself to fall forwards, but end up fall backwards and landing painfully on my butt.So… what actually is falling safely, and it is possible to fall safely backwards?