There are a few features that we need to look for. We need an application that's designed not just to be a text editor, to be a code editor. None of those are applications that are suitable for developing with code.
You may also have some word processing programs installed like Microsoft Word or OpenOffice or Pages. Mac OS X comes with the very simple text editor called Text Edit. The last thing is to make sure that you have a good text editor that you can use for writing your code. We're almost done with all the installations we need to be able to develop with Ruby on Rails.