You might have seen it before, tiny spots that enter your field of vision for no apparent reason. What you were seeing is likely floaters. Floaters make a shadow that looms over the retina and then the retina sends the information to the brain. The end result is an image being seen. What you see is tiny specks that move slowly across your field of vision. They are more likely to appear in special conditions such as the right amount of light or background. For example, when you look at an ordinary background such as a white wall you might be more likely to see floaters. They appear in all different shapes like dots, strings or cobwebs.
So I'm sure you are thinking this whole thing is kind of bizarre. But there is a good explanation for what these things are. There is a clear fluid in the eye called vitreous humor. Sometimes it becomes somewhat clumped together and causes floaters to occur. When you try to take a closer look at a floater they often disappear or jump from your field of vision. Eventually they will not show up as often as they once did and really are not harmful to you, in any way. The people who most often suffer with them are the elderly and people who are nearsighted.
People who see floaters might also have a problem with light flashes. Just as with floaters this is a trick of the eye where it seems like a bright flash of light enters your field of vision for a very short time. This phenomenom appears to be a line or arc of light which goes off in a certain direction. They normally appear to the side of your field of vision. When these show up in older people then they might be indicative of a detached retina.
You should still be cautious if you have floaters because they can be signs of a more serious condition like uveitus, retinal tears, high blood pressure or diabetes.
This makes it well worth your while to visit the eye doctor. If your floaters seem to get worse or become worrisome then make sure you have an eye exam as soon as possible.
When you see floaters it is a good idea to try and move your around by looking up or down. This can help to move the floaters from their current position. There is no medication available to treat this condition. If you have a severe case of floaters then surgery might be necessary to prevent blindness. Laser eye surgery and vitrectomy are the most common surgeries for floaters.