Have you heard about Mars, an Adobe project for representing PDF files in a XML-based format? A Mars file is essentially a ZIP file containing all the document’s assets (text, raster images, vector images, video, sound, fonts), in industry’s standard file formats such as SVG, PNG, JPG, JPG2000, OpenType, Xpath and XML.

But, wait a minute, does that mean that my font files will be placed inside a Mars file, and that anyone using an application to unzip it will get access to them?!?!
The answer is NO. The fonts are embedded in a Mars file — just like in a standard PDF file —, but you won’t find the fonts themselves inside it. Phew! :^)

If you’re the kind of person that needs to see in order to believe it (like I am), then have a look at the Mars file attached to the bottom of this post. Make sure you follow the instructions first!!

As you’ll see, when you look inside a Mars file, this is what you get: A bunch of files and folders, but definitely no OpenType (.ttf or .otf) font files.

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READ ME FIRST
The file below named Mars_file.pdf is a Mars file, BUT had to be disguised as a standard PDF file, because otherwise Typophile wouldn’t allow it to be uploaded and attached. To revert that change its current .pdf extension to .mars. The other file (PDF_file.pdf) is a standard PDF file.

If you want to peek inside the Mars file, just change its extension to .zip and unpack it with a regular unzip application.

To open a Mars file, go to the Mars Project page, download the plug-in for Adobe Reader 8 and install it. (You’ll need Adobe Reader 8 installed as well, obviously. But it’s free and much slick and faster than the previous versions, so go for it!)

In case you have Adobe Acrobat 8, download the Mars plug-in for it as well. This will add a new entry, named Adobe PDF in XML format, to the list of file formats that Acrobat is able to save. This new option enables you to save standard PDF files into Mars files.