Show Package Contents in Mac OS X

Bundles are a concept in Mac OS X whereby a specially named folder becomes what appears to casual users to simply be a file that can be copied as usual and often launched by double-clicking on it.

Other operating systems have file formats that are little more than containers for other files and in doing so keep those interesting resources out of your reach. (Okay, we have DMG but that’s more of a transportation mechanism like ZIP, TAR etc.)

To see the contents of one a bundle select it and just choose Show Package Contents from Finder’s context menu (hit the Task button in the toolbar, Ctrl-click or two-finger click).

The ones I find most interesting or useful are…

Application (.app)

All sorts of great resources can be found in here including icons, templates, sounds and the NIB’s for the user interface. Great for learning but consider the license before you take resources for your own application.

Garage Band project/template (.band, .wand)

Audio files of the instruments and output can be found inside.

Safari Download (.download)

An absolute gem if you are downloading audio or video files and want to watch or listen to what has downloaded so far.

Slideshow Screen Saver (.slideSaver)

Various images used in the slideshow.

iDVD theme (.theme)

Various images in tiff format and Quartz Composer compositions you could try using as screen-savers.

Time Machine (.inProgress)

If you have a partial backup with Time Machine and need a file it my have backed up this could be a life-saver.

iPhoto Library

Your original and modified photos from iPhoto and the XML data behind them.

iMovie project (.rcProject)

Contains a QuickTime movie of all the still images used in the project.


There are others to be found scattered across your file-system too:

Extension Type
.action Automator action
.bundle Bundle
.clr Colors
.colorPicker Color picker
.component Component
.dvdproj iDVD project
.fs Filesystem
.kext Kernel extension
.key Keynote presentation
.mdiimporter Spotlight importer
.nib Interface builder
.numbers Numbers spreadsheet
.osax Scripting addition
.pages Pages document
.plugin Plug-in
.pkg Installation package
.prefPan Preferences pane
.saver Screen saver
.wdgt Dashboard widget
.xcDataModel Core Data model
.xcodeproj Xcode Project

You might also want to check out this guide to examining bundles.


2 responses

  1. Avatar for Damon Stephenson

    Yeah, I noticed these when I was using Windows (Yeah, Office 2007 is better than Office 2004/2008 and Pages, so sue me). When you see a folder in Windows you don't recognise on your mac shares... it's a bit of a find!

    Damon Stephenson November 12, 2007
  2. Avatar for Tom

    Oddly enough, in every case I've seen, a .bundle file isn't actually a bundle, it's a single file.

    Which seems like a pretty awful idea to me.

    Tom December 13, 2007