stupid question, but what is initial d?

you guys rant and rave about it
but what is it? some type of race?

Japanese Street Racing Manga/Anime...

here go to this page for more info or search on search engine typign INital D.

http://www.geocities.com/yuri_seb/main.html

sweet
i just watched a few
i'm hooked
what are the cars they race? i'm not used to these non-american terms