Answer:
It holds most knowledge that has ever been said. But is not the brain, is not the head. To feathers and their masters, it's both bane and boonย One empty, and one full.
A hole in a pole, though I fill a hole in white. I'm used more by the day, and less by the night.
What is that which, though black itself, enlightens the world without burning?
My children are near and far. No matter that I know where they are. The gift I give them make their day. But if I were gone they would wander away.
Men have one, women two, and when they become family, itโs three. What is it?
People take me on walks and I run and have fun. What am I?