Floaters are actually tiny collections of cells or gel inside the vitreous cavity in the middle of your eye. These objects look like they are in front of your eye but they are actually floating inside the middle vitreous cavity. What you see are the shadows they cast on the retina (the thin nerve layer in the back of your eye that senses light and transmits this signal to your brain).
The Eye Encyclopedia written by Eye Physicians & Surgeons, sponsored by The American Academy of Ophthalmology
Eye Health information from The American Academy of Ophthalmology
Patient-information resource hosted by The American Society of Retina Specialists