Answer:
I have all the knowledge you have. But I am so small that I can fit into your hands. What am I?
You turn me over after you have traveled far. What am I?
Four leaves I have.
I am of several different kinds, but the one you pick doesn't do its job. What am I?
I have memories, but none of my own. Whatever's on my inside is what is shown. If I'm ever different, it's because you changed me. I feel like a decoration, here for you to arrange me. What am I?
What never gets any wetter no matter how hard it rains?