The write is about class variables in Ruby and in Smalltalk.The author, by looking for the origin of them (in order to have a better understanding of them), has discovered Smalltalk. He then explore the definition of the class and class instance variables both in Smalltalk and in Ruby.
http://patshaughnessy.net/2012/12/17/ruby-smalltalk-and-class-variables -- Miguel Moquillon
