What's the difference between PPC, Intel and Universal apps?

Just bought my MacBook (black, 120g, superdrive, £680 off eBay, yey!) and I want to get my head round what apps from my iBook I can install and how they’ll run.

PPC obviously won’t run directly but I think I read somewhere that MS Office for instance will run under Rosetta (or have I got this entirely round my neck?). Intel apps presumably run natively; but does Universal essentially mean a disk image with two sets of code, one for PPC and one for Intel? Or is it a way of wrapping the PPC code up so it’ll run on an Intel, and therefore probably a bit slower?

And while I’m about it - Bootcamp. Am I likely to be able to run an OEM copy of XP under it or do I have to get virgin installation disks?

PPC apps run under Rosetta, yes. By most accounts, non-intensive apps like Office run almost as fast as they would natively, so you’ll hardly notice.

Almost. The actual app bundle contains two sets of code, one for PPC, one for Intel. So the app file takes up more disk space, but that’s all. There’s no operational slowdown because only the version of the app which runs natively is launched. The other version is essentially idle code that will do nothing other than take up a bit of disk space.

Doubtful an OEM copy of Windoze would install, and it certainly wouldn’t be legal. You’ll need a retail copy, I believe.

Antony has pretty much answered your query, but I’ll add that you don’t really need to worry about Rosetta. It’s not like Classic which would make a big furore about firing up and feel completely separate from everything else. When you launch a PPC app on an Intel machine, you won’t notice - Rosetta do everything without you even noticing that Rosetta is there.

Note that there are some annoyances in that some companies have been very slow to update to Universal (Universal apps run natively - and thus as fast and efficiently as possible - on both PPC and Intel architectures). As you note, Office isn’t Universal and won’t be until Office 2008. It runs fine for me, though it is slow opening up (I’m not sure if this is because it is PPC or just because it is Office :slight_smile: ). Also, Shockwave plugins still don’t work as Shockwave hasn’t been made Universal yet… Groan. (Though if you need to view Shockwave content you can force Safari to run via Rosetta by checking the option in the Get Info pane in the Finder for Safari.)

As an end-user you don’t really need to worry too much other than trying to ensure that you buy Universal apps from now on where possible.

All the best,

Thanks… I’m mainly going to be interested to see if NeoOffice runs at a speed which means I can actually use it…

In case you didn’t already know, NeoOffice comes in either PPC or Intel, not Universal. Make sure you download the right one.

One thing I’ve wondered about, sometimes when trying out old shareware it doesn’t say if it’s universal or not, is there a way to know if a process runs under rosetta or not?

In the info window you can see if it’s an PowerPC, Intel or Universal app. It’s shown in brackets in the uppermost tab. Most of “old shareware” should be PPC, though. :wink:


I have noticed stability problems with excessively complicated applications running under Rosetta. Specifically, older versions of Adobe Photoshop and InDesign. These are hardly typical applications though. Most things run flawlessly, and the base speed bump of the newer computers makes whatever emulation sacrifice extremely minimal.

If you’re going to use MS Office 2004 for any reason, be sure and run the updates. Word used to crash every once in a while, but so far ( :::knock on wood::: ) it seems stable.

Other than that, the whole Rosetta thing is pretty much invisible to the user. You don’t really know it’s being invoked. The programs just run. :wink: