Ruby Style Guide

%w(literal string array)

%i(literal symbol array)

Use Hash#fetch. It will raise a KeyError, making the problem obvious

Object#to_s method is invoked automatically when it’s interpolated object.

eg: message = "This is the #{object}."

Use String#<<, it mutates the original string and is faster

String#+ will create a new string

Create a symbol with spaces in it :"some string"

####Questions

What’s the meaning that Ruby 1.9 hashes are ordered