Oh, I need to know...what is the color difference between blue-indigo-violet? I don't know what color indigo is. Like a light colored denim?
OK this is a weee bit complex, but not really. Here look at this color wheel.
See the color in between, Blue-Violet?
Blue-Violet is Indigo
Here is a example with the Hex numbers used for HTML but it gives you a good idea of Indigo
And then there are some people who just have got it Bass-ackward and think Magenta is Indigo.