Answer:
I can travel from there to here by disappearing, and here to there by reappearing.
Thousands of these come together to make a digital image. What is it?
Each morning I appear to lie at your feet, all day I follow no matter how fast you run. Yet I nearly perish in the midday sun.
My life can be measured in hours. I serve by being devoured. Thin, I am quick. Fat, I am slow. Wind is my foe.
Whoever makes it, tells it not. Whoever takes it, knows it not. Whoever knows it, wants it not
What covers its face with its hands, speaks no language, yet most known what it's saying?