Let’s talk about Apple’s iWork software. Apple’s Office Suite of applications was first released in 2005 and provided a WordProcessor (Pages), Presentations (Keynote), and a little later, Spreadsheet (Numbers). They are exclusive to the Macintosh and iOS devices.

iWork was released in a few different versions. They get a little confusing as each application has its own version which all seemed to unify and stabilize in 2020. Here is a matrix of major versions.

Version	Package or ZIP
iWork ’05	Package
iWork ’06	Package
iWork ’08	Package
iWork ’09	ZIP
iWork 2013	Package
iWork 2014	ZIP
iWork 2019	ZIP
iWork 2020	ZIP

You may already be aware but MacOS can sometimes be weird. I use the term weird in a loving, sometimes proud way, but I admit, there was some “odd” choices made in regards to how applications and documents are used and stored files on a Mac.

On early Macintosh computers Apple used an interesting method of storing resources for applications and some file formats. The Resource Fork for an application contained all the “resources” needed to run in the operating system. It would contain all the icons, warning screens, graphics, sounds, etc. This held true until Mac OS X came along and then Apple started using a bundle or package format. Still in use today, what appears to be a single file or application is actually a folder of all the resources needed to run the application.

By right clicking or control clicking on the icon you can open the folder and see all the contents which make up the Application.

Nifty right? The MacOS which knows which extensions to treat as a package. If you were to move the application over to another system it would be a folder with the extension “.app”.

For an application I can see how this makes sense as it will only execute in the MacOS environment. The problem comes in when you use the same package method for the documents the application creates.

So instead of a single “file” with a bytestream, you get a folder of files which make up the file format. Here is Apple’s description:

Document Packages

If your document file formats are getting too complex to manage because of several disparate types of data, you might consider adopting a package format for your documents. Document packages give the illusion of a single document to users but provide you with flexibility in how you store the document data internally. Especially if you use several different types of standard data formats, such as JPEG, GIF, or XML, document packages make accessing and managing that data much easier.

Apple actually defines two similar methods:

Although bundles and packages are sometimes referred to interchangeably, they actually represent very distinct concepts:

• A package is any directory that the Finder presents to the user as if it were a single file.
• A bundle is a directory with a standardized hierarchical structure that holds executable code and the resources used by that code.

A couple years ago a processed digital collection made its way down to me. It had been processed by a new digital archivist and when I went to prepare the collection for preservation, I found a folder with the extension .pages and inside the folder a whole directory of files. Many of which they had renamed and arranged. Needless to say, I had to track down the original disk so I could properly preserve the file.

So looking back at the earlier table, iWork switched back and forth between the package format and a ZIP container. For preservation purposes, the ZIP container is easier to maintain outside the MacOS. Lets look a little closer at each. If you would like to follow along I have copied a few samples onto a hybrid ISO.

iWork ’05 through iWork ’08 used the same package format and structure. Because they are a package format, they are difficult to preserve as original files. I suppose you could zip them up, but probably the best option is to open with a current version of Pages and save to the newer ZIP container format.

tree iWork08/Keynote-06.key 
├── Contents
│   └── PkgInfo
├── QuickLook
│   └── Thumbnail.jpg
├── index.apxl.gz
└── theme-files
    ├── Blue 2.jpg
    ├── Blue 2.tif
    ├── Cool Gray-2.jpg
    ├── Cool Gray.tif
    ├── Green-8.jpg
    ├── Green.tif
    ├── Headlines_bullet.pdf
    ├── Headlines_star.pdf
    ├── Orange 2.tif
    ├── Orange_2.jpg
    ├── Purple-6.jpg
    ├── Purple.tif
    ├── Red.jpg
    ├── Red.tif
    ├── endpoints.pdf
    └── headlines_hi-res.jpg

iWork ’09 changed this practice. The documents saved from Pages, Keynote, and Numbers were contained in a ZIP file and can be identified using the PRONOM registry container signatures.

filename : 'iWork 2013/Pages2013-Sample09.pages'
filesize : 105900
modified : 2019-11-21T20:36:00-07:00
matches  :
  - ns      : 'pronom'
    id      : 'fmt/1439'
    format  : 'Apple iWork Pages'
    version : '09'
    class   : 'Word Processor'
    basis   : 'extension match pages; container name index.xml with byte match at 195, 76' 

Sample09.pages
Type = zip
WARNINGS:
Headers Error
Physical Size = 105900

   Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  ------------------------
2019-11-21 20:36:00 .....       364773        22413  index.xml
2019-11-21 20:36:00 .....         7007         7007  Hardcover_bullet_black.png
2019-11-21 20:36:00 .....        69176        69176  Simple_Noise_2x.jpg
2019-11-21 20:36:00 .....          232          232  buildVersionHistory.plist
2019-11-21 20:36:00 .....         6406         6406  QuickLook/Thumbnail.png
------------------- ----- ------------ ------------  ------------------------
2019-11-21 20:36:00             447594       105234  5 files

Then Apple went back to a Package format with iWork 2013. For reasons unknown. But the content and structure changed. Its a package format with a Index.zip instead of index.xml

Pages2013-Sample.pages
├── Data
│   └── Hardcover_bullet_black-13.png
├── Index.zip
├── Metadata
│   ├── BuildVersionHistory.plist
│   ├── DocumentIdentifier
│   └── Properties.plist
├── preview-micro.jpg
├── preview-web.jpg
└── preview.jpg

3 directories, 8 files

The ZIP within the package contains a new Apple format. IWA

Pages2013-Sample.pages/Index.zip
Type = zip
Physical Size = 39361

   Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  ------------------------
2019-11-21 20:47:14 .....         3860         3860  Index/Document.iwa
2019-11-21 20:47:14 .....           26           26  Index/Tables/DataList.iwa
2019-11-21 20:47:14 .....          336          336  Index/ViewState.iwa
2019-11-21 20:47:14 .....          160          160  Index/CalculationEngine.iwa
2019-11-21 20:47:14 .....          121          121  Index/DocumentStylesheet.iwa
2019-11-21 20:47:14 .....        31931        31931  Index/ThemeStylesheet.iwa
2019-11-21 20:47:14 .....           22           22  Index/AnnotationAuthorStorage.iwa
2019-11-21 20:47:14 .....         1889         1889  Index/Metadata.iwa
------------------- ----- ------------ ------------  ------------------------
2019-11-21 20:47:14              38345        38345  8 files

Luckily Apple came to their senses and went back to the ZIP container format for iWork 2014 and later. The container signature looks for the IWA file Apple started using with iWork 2013.

filename : 'iWork 2014/Pages2014-Sample.pages'
filesize : 66256
modified : 2019-11-22T00:03:56-07:00
errors   : 
matches  :
  - ns      : 'pronom'
    id      : 'fmt/1441'
    format  : 'Apple iWork Document'
    version : '14'
    class   : 'Presentation, Spreadsheet, Word Processor'
    basis   : 'extension match pages; container name Index/Document.iwa with byte match at 16, 6; name Metadata/Properties.plist with name only'

Path = iWork 2014/Pages2014-Sample.pages
Type = zip
Physical Size = 66256

   Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  ------------------------
2019-11-22 00:03:54 .....         3930         3930  Index/Document.iwa
2019-11-22 00:03:54 .....          364          364  Index/ViewState.iwa
2019-11-22 00:03:54 .....          206          206  Index/CalculationEngine.iwa
2019-11-22 00:03:54 .....        33573        33573  Index/DocumentStylesheet.iwa
2019-11-22 00:03:54 .....           22           22  Index/AnnotationAuthorStorage.iwa
2019-11-22 00:03:54 .....           23           23  Index/DocumentMetadata.iwa
2019-11-22 00:03:54 .....         8761         8761  Index/Metadata.iwa
2019-11-22 00:03:54 .....          322          322  Metadata/Properties.plist
2019-11-22 00:03:54 .....           36           36  Metadata/DocumentIdentifier
2019-11-22 00:03:54 .....          273          273  Metadata/BuildVersionHistory.plist
2019-11-22 00:03:54 .....        14611        14611  preview.jpg
2019-11-22 00:03:54 .....          838          838  preview-micro.jpg
2019-11-22 00:03:54 .....         1571         1571  preview-web.jpg
------------------- ----- ------------ ------------  ------------------------
2019-11-22 00:03:54              64530        64530  13 files

Now iWork was not the only Apple software to use the Package/Bundle format for their documents. Be advised the following software may save to the package format.

• Aperture Library
• Final Cut Pro X
• Soundtrack Pro
• Apple Motion
• Garageband Project
• DVD Studio Pro
• iMovie Project
• Logic Pro Project
• RTFd document

I remember a few years ago, Trent Reznor (NIN) decided to release a few of his tracks in the Garageband format. A little harder to find these days, but the good old wayback machine kept a copy for us! Grab them here. Be warned, they may be in the package format. Thanks Apple!