 It produces hyperlinked HTML files from annotated Haskell (the documentation is embedded in comments) source files, with additional information extracted from type annotations; it supports only partially generating documentation in SGML.It is often used in conjunction with darcs and Cabal.It is dependent on Glasgow Haskell Compiler (GHC), using a modified form of the HsParser (written in Happy) parser for Haskell included in GHC.