Curves - More in depth

So we have the basics down. Let's really explore curves today and get a true inside understanding of the tool.
Read and follow this article on curves . I know it's long, but it's really good. Actually read the whole thing, then you're going to create three rollover images that will show the image, the histogram and then the curves for that image - just like the tutorial does. You are going to demonstrate what different curve adjustments do to the image and the resulting histogram.