The term "cross platform" primarily refers to data or media files which can be used or viewed on both Macs and PCs. For example, MPEG-1 video files will play on both Macs and PCs but PC AVIs can be problematic. Therefore MPEG-1 is a cross platform media format and AVI is not. In practise most file types are cross platform providing you observe the simple rules outlined on this page. Here are some examples ...
.dcr, .dir (Director)
.txt, .rtf (text)
.psd (Photoshop) etc
Final Cut Pro projects
The short answer is ... when you have to move files between, or view files on, PCs and Macs, such as when you make a web site.
Click here for information on publishing projects including cross platform issues.
There are several issues that you need to be aware of when making cross platform files.
The ISO9660 standard defines the file structure of a cross platform CDROM (PC and Mac).
Click here to read about the strict rules you must observe to ensure files are handled correctly by the widest number of PCs and Macs.
Gamma is to do with screens and effects the way that computers display colour. For example ...
Most computer users have a range of fonts installed but they don't all have the same fonts. This can change the way that your files (such as web pages and Word docs) appear when moved between computers.
To get around this problem you can do several things ...