The eye floaters are just deposits or condensation in the vitreous jelly of the eye. Usually, people use the words floaters to describe the noticeable floating spots in their eyes. And the floaters may just in one eyes, it may also occurs to both of eyes. Still some people also describe floaters as straight and curved lines, strings, or "O" or "C" shaped blobs. If you want to know the images of eye floaters, you may search it in Google Images.
You said you have read lots of information about floaters, so I believe you have known phenomenons of floaters. Floaters is just a description of the phenomenon, is not a specific disease. Patients' eyes will appear dark shadow, and the shadow will round with the eyeball's moving, just like floaters. Its shape is round, oval, point like, linear, etc. Often, when patients see the blue sky, white wall or other more bright beautiful background, it is easier to discovered.
There are black spots appear before people who have floaters, and the black spots are flying with the rotation of the eyes, which like the flying mosquitoes. In general, the shapes are round, oval, punctuate, or linear. The common situation is when you look at the blue sky, white wall and other bright background, you can easily see it. So the black spots and lines which you said are symptoms of floaters.