2004 was written back when the all Mac's ran on a Power PC (PPC) processor.
Since that time, Apple moved on to using Intel Processors which operating in a completely different way, but achieve the same end result.
As a result of this moved to the Intel processor, software developers started to produce a method of coding their programs so that they would run, natively, on both types of processors. The resulting code is known as Universal Binary. It is essentially two different codes in the one package and each type of processor runs the one that suits it.

You may have gathered that Universal has nothing to do with cross platform compatibility. Office has usually behaved very well, on both platforms, in being able to open and display files that were created using the other platform. Win/Mac & Mac/Win. This is still the case.

Judging by some of the feedback being seen in some forums, Office 2008 is not a major step forward for the suite, in fact it appears to some to be a step back. Claims of slow running and over-bloat (surely not) are common.

Alternatives to Office include Open Office and Neo Office. Both are free and both have decent compatibility with MS Office on both platforms.

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