Answer:
you need thousands of me to create a digital image.
What goes through towns and over hills but never moves?
Everyone in the world needs me. They generously give me but never take me. What am I?
I run up and down the stairs without moving
I'm the source of all emotion but I'm caged in a white prison.
It has no top or bottom, but it can hold flesh, bones, and blood all at the same time.