How to learn Haskell
This is a recommended path for learning Haskell based on experience helping others.
For non-English speakers
Don't sweat the stuff you don't understand immediately. Keep moving!
Our IRC channel is
#haskell-beginners on Freenode.
IRC web client here.
The haskell mailing lists.
See the community guidelines to understand the conduct that is expected in the IRC channel. You'll get a warning if you're not obviously trolling, but be aware the channel is exclusively for those learning or teaching Haskell.
What are Haskell, GHC, and Cabal?
Haskell is a programming language as laid out in the reports, most recent one being in 2010. The report is available as the onlinereport.
GHC is the most popular way to work in the Haskell language. It includes a compiler, REPL (interpreter), package management, and other things besides.
Cabal does project management and dependency resolution. It's how you'll install projects, typically into their own sandbox.
Cabal is equivalent to Ruby's Bundler, Python's pip, Node's NPM, Maven, etc. GHC manages packaging itself, Cabal chooses what versions to install.
See the install instructions for how to get GHC & Cabal installed.
How should I learn Haskell?
The core recommendation is to read the lectures and complete all exercises/homework for the Spring 13 version of cis194 followed by the NICTA course. Both are linked below. Everything else can be considered optional and is mentioned so you know where to look.
Yorgey's cis194 course
Do this first, this is the primary way we recommend being introduced to Haskell.
Brent Yorgey's course is the best I've found so far. This course is valuable as it will not only equip you to write basic Haskell but also help you to understand parser combinators.
The only reason you shouldn't start with cis194 is if you are not a programmer or are an inexperienced one. If that's the case, start with Thompson's book and transition to cis194.
This is the course we recommend doing after Yorgey's cis194 course
Available on github here.
This will reinforce and give you experience directly implementing the abstractions introduced in cis194, this is practice which is critical to becoming comfortable with everyday uses of Functor/Applicative/Monad/etc. in Haskell. Doing cis194 and then the NICTA course represents the core recommendation of my guide and is how we teach everyone Haskell.
Supplementary course after cis194 and the NICTA course
Provides more material on intermediate topics
cs240h is available online.
This is Bryan O'Sullivan's online course from the class he teaches at Stanford. If you don't know who he is, take a gander at half the libraries any Haskell application ends up needing and his name is on it. Of particular note if you've already done the Yorgey course are the modules on phantom types, information flow control, language extensions, concurrency, pipes, and lenses.
Resources for specific topics in Haskell
These resources are not vetted or tested with learners as cis194 and NICTA course have been, but they're linked in the topic listing so you have ideas on where to begin. This includes things like intermediate/advanced concepts and subjects like tooling and text editors.
Extended Reading list
Some are already included here
Hosted in this repository here.
These are actually pretty important and helpful. Look here for deep dives on a variety of topics.