The hierarchy of numeric typeclasses in Haskell

Some time ago I posted this in my Russian blog. Re-posting it here, for it's inconvenient to not be able to find it when googling in English. I use it for reference :-)

Haskell Numeric typeclasses

Non-abstract types are gathered together in gray frames. Polymorphic types and type classes have rounded boxes. Their possible type parameters are indicated with inversed rhombus arrows.