Thanks that helps. So it was probably just the way I passed the command...
This is what I typed "sudo gem install rails 4.2.1 --no-ri --no-rdoc", does that look funny?
Should I be concerned about the contents of this error message "Could not find a valid gem" or is it simply nothing more than what you just said?
What I wanted to do was pass the command with head in it but I don't know the syntax for that and I couldn't find a reference to it that quickly. Does anyone know the proper way to pass the command for get head?