revial: They're the base academical components of any reagents you find. Though, since you seem to have played Witcher 1, I'm not sure you're really asking or simply expressing annoyance in the form of a question, since it's the exact same thing from the first game.
And, yes, you need to keep the formulae/diagrams. You can read books and then get rid of them though. And yes, it's an obvious step back from the first game.
Yes I have played the first Witcher. I'm asking an honest question, which explains my annoyance regarding why those 9 circular icons are not explained in the game manual. I seem to understand that the icons are some sort of classification, and I probably could get away without knowing what they mean, but I would like to know if the classifications have any impact on my creating potions/bombs/oils.
I don't remember any of those 9 circular symbols in the Witcher 1, though to be honest I just created whatever potions I could with the ingredients on hand. I didn't actively go searching for specific ingredients for formulas.
edit:
OH. I didn't know you could scroll through those icons. So each symbol/reagent shows the list of ingredients that contain it. I only remember Virtroil and Rebis from Witcher 1 so I had no clue what Fulgur was supposed to mean.