Wikipedia, it used to be an island and there's a lot of history behind the name But what I could notice when I was there about what is said in Wikipedia is the fact that this used to be a place for amusement parks. They say that before World War II this was the main destination in the US if you wanted to go to amusement parks with roller coasters and similar kind of rides. After some years of neglect it lost its popularity and even though when there are still some parks and rides there, it's not the top place anymore. I could personally see one of the old wooden roller coasters (look at the first picture) beside the New York Aquarium, which is the actual place that moved me and a friend to visit Coney Island in southern Brooklyn last year.
Jacques Costeau when I was a child and used to watch his journeys on TV. At the end of the day we walked through the empty beach of this in another time acclaimed iconic place named Coney Island.
Update (Apr 19, 2011): I visited Coney Island again last Sunday and this time under some peer pressure I had a ride in the Cyclone, the wooden roller coaster that can be seen in the first image in this post. I can say it is a great experience to ride this engineering monument that dates back to 1927!