This document outlines coding style guidelines for various aspects of Ruby code including indentation, whitespace, naming conventions, comments, and other stylistic elements. It discusses formatting recommendations for indentation, line lengths, alignment, blank lines and spaces, trailing whitespace, declarations, dead code, and use of parentheses. It also provides tips for commit messages, and style guidelines for models, views, and controllers in Ruby on Rails. The document is intended as a reference for writing clean, readable Ruby code.