This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.
# Gem::RemoteError < Gem::Exception (from ruby core) --- Signals that a remote operation cannot be conducted, probably due to not being connected (or just not finding host). ---
This is MURDOC! A Ruby documentation browser inspired by Smalltalk-80. It allows you to learn about Ruby by browsing through its class hierarchies, and see any of its methods.