or are they the same thing?

wilton course 11 books. says your pieces will be stronger and shinnier ,you can use royal icing the same way.. but , it won,t be as strong as color flow.. always have a "pillow look" when using either one.. hth

You can use them both for making images to go on top of your cake, but you do not want to pipe color flow onto your cake as for decorations or use cf to make flowers. Color flow taste nasty.
I made two skulls to place on top of my cakes, one is with CF, the other one was RI ( flaming skull) you can see them in my pics. I would only use CF for this purpose.
I have read in my wiltons book were the instructions state to use CF on a cookie, I do not like the taste so I use RI. Hope I was of some help.