The spots you are seeing are called floaters. Floaters are small clumps of gel that form in the clear jelly-like fluid that fills the inside cavity of the eye (the vitreous). Although they appear to be in front of the eye, they are actually floating in the fluid inside the eye and are seen as shadows by the retina – the seeing part of the eye. They are usually more noticeable when you are reading a book or looking at a plain background.