I will echo the choir here that states that Category theory is not Haskell. Category theory gave Haskell some neat tricks, but its not necessary to understand i

I will echo the choir here that states that Category theory is not Haskell. Category theory gave Haskell some neat tricks, but its not necessary to understand it to do anything practical. Category theory is so abstract and general that it is unlikely to come up with any grand solutions unless you are phd'ing. If you enjoy it anyway: I like (http://www.haskell.org/haskellwiki/Typeclassopedia http://www.haskell.org/haskellwiki/Typeclassopedia) for how it discusses how the different type classes in Haskell relate. I found this a lot more practical coming from this direction but your taste may vary. I'd also highly recommend going through Types and Progrmaming Languages by Pierce (http://www.cis.upenn.edu/~bcpierce/tapl/ http://www.cis.upenn.edu/~bcpierce/tapl/) if you are interested in the area. This gives you a good background on type system stuff. There are tons more links to category theory stuff here (http://mathoverflow.net/questions/903/resources-for-learning-practical-category-theory http://mathoverflow.net/questions/903/resources-for-learning...)