[Haskell-cafe] AbstractDataType question

So in the wiki on AbstractDataType ( http://haskell.org/hawiki/AbstractDataType ) it gives the following example: data Tree a = Nil | Node { left :: Tree a, value :: a, right :: Tree a } The part where I am confused is with the use of '{' and '}' my reference book is apparently out of date as it states that Haskell doesn't even use those characters :) Could someone point me to some documentation on whats being created here and how its used? thank you Jason