Homebrew is a great little package manager for OS X. If you haven't already, installing it is pretty easy:
ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"
This list is meant to be a both a quick guide and reference for further research into these topics. It's basically a summary of that comp sci course you never took or forgot about, so there's no way it can cover everything in depth. It also will be available as a gist on Github for everyone to edit and add to.
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