Scheme itself has umpteen different "implementations", which share most of
their fundamentals, but have slightly different extensions and interact with
-the operating system differently. One major implementation is called Racket,
+the operating system differently. One major implementation is called [Racket](http://racket-lang.org),
and that is what we recommend you use. (A few years back they were called PLT Scheme, but then
they changed their name to Racket.)
If you're already using or comfortable with
The current version of OCaml is 4.02.1 (released October 2014).
-Another instruction page focuses on [OPAM](http://ocaml.org/docs/install.html), also [this](https://opam.ocaml.org).
+* *Another instruction page focuses on [OPAM](http://ocaml.org/docs/install.html), also [this](https://opam.ocaml.org).*
+
+* *[More details about installing OCaml on Macs, if needed](http://cocan.org/getting_started_with_ocaml_on_mac_os_x)*
* In your web browser:
There is a (slow, bare-bones) version of OCaml available for online use at <http://try.ocamlpro.com/>.
+
* **To install in Windows**
Go to <http://caml.inria.fr/download.en.html>.
you a nice history of the commands you've already typed, which you can scroll up and down in with your
keyboard arrows.
-* [More details about installing OCaml on Macs, if needed](http://cocan.org/getting_started_with_ocaml_on_mac_os_x)
-
* **To install on Linux**
Use your packaging system, for example, open a Terminal and
## Getting Haskell ##
-This last step is less crucial than the others, since we will be focusing
+This last installation is less crucial than the others, since we will be focusing
primarily on Scheme and OCaml. However we, and the readings you come across,
will sometimes mention Haskell, so it might be worth your installing this too,
so that you have it available to play around with.
There is a (slow, bare-bones) version of Haskell available for online use at <http://tryhaskell.org/>.
-sudo apk-get install haskell-platform
+Like Scheme, Haskell has a couple of different implementations. The dominant one, and the one we recommend you install, is called [GHC](https://wiki.haskell.org/GHC), short for "Glasgow Haskell Compiler". To install this on your machine, there are a couple of different strategies. It's helpful to understand some lingo as you begin this process:
+
+* As mentioned, **GHC** is the main Haskell engine or compiler you'll be installing. The current version is 7.8.4, from December 2014.
+* **gcc** and **llvm/clang** and **Xcode** and **MinGW** are names for other compilers on different systems. Oftentimes these will be used during the installation process to get GHC up and running. Some of the strategies described below will help you install these if they're not already on your machine.
+* **alex** and **happy** and **haddock** are names of various Haskell helper programs that GHC uses to get up and running.
+* **cabal** is a "package manager" for Haskell. It allows you to install libraries or extensions that other people have built. (Usually those are published at the [Hackage](http://hackage.haskell.org) web site. Some of these are experimental and may not always work; others are quite fundamental and are almost de facto parts of what people expect in a Haskell system.
+* **[Haskell Platform](https://www.haskell.org/platform)** is a standard bundle that includes a fixed version of GHC, plus fixed versions of some of the most popular libraries or extensions. This is updated once or twice a year. The current version is 2014.2.0.0, from August 2014. It includes GHC version 7.8.3.
+
+The easiest way to get up and running with Haskell/GHC is to install the Haskell Platform. Here's how to do that on Ubuntu or Debian Linux:
+
+* In a Terminal, type `sudo apk-get install haskell-platform`.
+
+On a Mac without MacPorts:
+
+* \<Instructions>
+* <https://github.com/pittsburgh-haskell/haskell-installation>
+
+On a Mac with MacPorts:
+
+* \<Instructions>
+
+On Windows:
-<https://github.com/pittsburgh-haskell/haskell-installation>
+* \<Instructions>
-<https://www.haskell.org/platform>
-Getting started: <https://wiki.haskell.org/Haskell_in_5_steps>
+* It's useful to know about the general [Haskell wiki](https://wiki.haskell.org) (not restricted to just GHC). They have a [Getting Started](https://wiki.haskell.org/Haskell_in_5_steps) page, which also recommends that you install the Haskell Platform.
+* <new-www.haskell.org/downloads>