What Am I Riddles

Question: what does not move outside (the surface)but moves inside ?

Question: Only one color, but not one size, Stuck at the bottom, yet easily flies, Present in sun, but not in rain, Doing no harm, and feeling no pain. What am I?

Question: I am just an ordinary word that comes in form of a man, accepted by many but rejected by a few, not felt by many but felt by a few, not shown by many but shown by a few. What am I?

Question: When you close it, you see mysterious and funny looking images. But if you open it, the mysterious images are gone. What Am I?

Question: I can be seen, I can be not. Thanks to me, you'll fall in love. I mostly am sweet, but once I were sour. You can receive me, you can't just buy me. You only can send me, or simply share me. What Could I be?