[hennaz]

From what I learned, it is completely unacceptable for anyone to call a black guy the "N-word", but ironically, it is OK for blacks to refer to as each other using that word. I've always found that weird.
As for the word "negro", it isn't as offensive as the previous racial slur, but is still considered insulting. The only racial terms for white people I don't like are the Cantonese term "gweilo" (ghost guy) and the Japanese term "gaijin" (outsider). They probably should not be taken seriously as the slurs for blacks mentioned above, but I would never be happy if a Hong Konger or Japanese called me by "gweilo" or "gaijin" respectively.