Spots called floaters are small, semi-transparent or cloudy specks or particles within the vitreous, the clear, jelly-like fluid that fills the inside of your eyes. They appear as specks of various shapes and sizes, threadlike strands or cobwebs. Since they are within your eyes, they move as your eyes move and seem to dart away when you try to look at them directly.
Spots are often caused by small flecks of protein or other matter trapped during the formation of your eyes before birth. They can also result from deterioration of the vitreous fluid, due to aging; or from certain eye diseases or injuries.
Most spots are not harmful and rarely limit vision and many fade over time. However, suddenly seeing new floaters, or floaters accompanied by flashes of light or peripheral vision loss, may indicate a retinal detachment. You should see your eye doctor for a comprehensive examination when you notice sudden changes or see increases in them to determine if what you are seeing is harmless or are symptoms of a more serious problem that requires treatment.