Why do people have black spots on their tongues

I don't know because I have never heard of it.. I don't have black spots on my tongue.

I've heard that it was a condition known as hairy tongue or something like that. Sounds strange, but maybe you could look hairy tongue up in the internet and see what you get. Let me know.

why do people have black spots on thier tongues
I found this:

http://archfami.ama-assn.org/cgi/reprint/9/3/219.pdf

Apparently, black taste buds on dark skinned people is common and not of consequence. Hairy tongue seems to be a disease. Over 15 years ago, I had a dentist tell me , an African American, that I had hairy tongue because I had a small group of dark taste buds on the tip of my tongue. All these years I believed him and was embarrassed to show my tongue. Now I find out he was wrong. I have seen this on other people of my heritage and wondered if they had it too. India Arie, a famous singer has them. Thanks for asking this question.