1. A derogatory term used against Africans but yet has been made popular in today's culture.

2. It can also mean a black person that is useless. Just like calling a white person a cracker or a Hispanic person a spic, i.e. all niggers are black but not all black people are niggers.
So yes, There is a difference between a black person and a nigger.

A fully grown niglet

A word that everyone else is afraid to define except in utter seriousness, for fear of being branded a rascist, in total ignorance of the colloquial usage of the word, its characterization in popular culture, and the populations of people it is used most by.

a term that is racist, as long as the speaker of it is not black. Forbidden on most all of television and other forms of public entertainment, at times referenced to as the "n-word". However, "cracker", a term racist against whites, is a completely acceptable term used in any context of any national broadcast...hmm...

nigga, niggah etc. al.(noun)1.describes an ignorant, uneducated, foolish individual regardless of race, color, religion, sexual orientation, etc.
2. endearing term between two or more individual to describe a friendship or bond.

Slang description for slaves who were brought mostly from West Africa by the Dutch, English, and Portuguese from what was then a huge "Nigerian Basin" which makes up part of the countries of Nigeria and Niger today.

Used as a disparaging term for a member of any dark-skinned people.

nigger is to black person as redneck is to white person