You may sometimes see small specks or clouds moving in your field of vision. They are called floaters. You can often see them when looking at a plain background, like a blank wall or blue sky. Floaters are actually tiny clumps of gel or cells inside the vitreous, the clear jelly-like fluid that fills the inside of your eye.
Floaters may look like specks, strands, webs or other shapes. Actually, what you are seeing are the shadows of floaters cast on the retina, the light-sensitive part of the eye.