Floaters are small, and semi-transparent or cloudy particles of various shapes and sizes or like cobwebs that float within the vitreous, which is the jelly-like fluid that fills the inner portion of your eyes. Floaters are usually harmless and are seen by many of us at one time or another. They are frequently visible when you are looking at a plain lighted background like a white wall, a blue sky or the white pages of a book.
There are a number of possible causes for floaters. Firstly, deterioration of the vitreous may cause floaters to develop. This can be part of natural aging process. Secondly, certain eye disease or injuries can cause floaters. Thirdly, there may be small flecks of protein or other matter that were trapped during the formation of your eyes before birth and remain suspended in the clear fluid of the vitreous. Sometimes they can be caused by retinal detachment which is a medical emergency that requires immediate attention. In this case, people notice a sudden increase in the floaters or flashes of lights or shadow/curtain covering parts of visual field.