If you already are comfortable with a programming editor, use that one. Just double-check with an instructor to make sure it will work.

If you are unsure, we suggest Sublime Text 2

1. Open your Editor

Windows

To start Sublime Text 2, please select it from the Start Menu under 'All Programs'.

OSX

1. Double-click the Applications folder in the disk image, or navigate to Applications in the left panel of Finder.
2. In Applications, scroll down until you see Sublime Text 2.
3. Double-click Sublime Text 2 to open the editor.

Linux

Type this in the Terminal to start Sublime:

/usr/bin/sublime-text

Or, you can use your GUI's menus, as an icon has most likely been installed.

2. Set some basic preferences

Sublime Text 2 reads its preferences from text files. This means you can easily edit settings, check your settings into version control, or share settings with copy & paste. That's what we're going to do with some common preferences for Rubyists.

Open up User Settings (Sublime Text 2 > Preferences > Settings - User) and paste in these preferences:

{
  "tab_size": 2,
  "translate_tabs_to_spaces": true,
  "trim_trailing_white_space_on_save": true,
  "ensure_newline_at_eof_on_save": true,
  "save_on_focus_lost": true
}

Save the User Settings file (File > Save). Your new preferences are now in effect.

Success!

Now you have an editor that you can use to open any text file, including Ruby programs.

Next Step

You've got everything! Proceed to the Checklist.