partiell quote, "Do black people discriminate against other black people based on skin color?

Yes and No.

Yes, there is discrimination by Shades of blackness: You see, the fact that Barack Obama or Halle Berry are ‘black’ complicates the whole notion of blackness in the context of racial discussions. To this extent, there are ‘blacks’ that are not black enough to other blacks and obviously not white enough to whites. These unlimited shades of black (or white) sometimes discriminate against each other.
No; not based on skin color but on “origin”: There are blacks from Africa, there are Afro-Americans (to include “Afro-Europeans”), and there are blacks from South America. Whereas the world tends to describe people in terms of race, people themselves may choose to describe themselves in terms of their nationalities or geographical locations of their birth. Therefore, you have blacks who are British, American or Brazilian, and they see themselves as such before any other label. And then, of course, Africans (yes, the world calls us a country). I have experienced discrimination on such grounds by other blacks. Africans in the diaspora are the major culprits when it comes to this type of discrimination.
Yes, again, but within Africa. In Africa, ‘lighter’ is better. This is more pronounced among women, though it is exacerbated by the men who love (or are supposed to) them. Most African men tend to prefer this complexion:"