NOTE: The following applies only to Mac OS X 10.6 (Snow Leopard) or later.

1. Open Activity Monitor.
2. From the menu bar, select View > Columns > Kind.
3. In the Activity Monitor window, change the drop down menu at the top to All Processes, or to that process in which you're most interested.
4. Now, in the Kind column, you will see there are 3 Kinds listed:
   1. PowerPC
   2. Intel
   3. Intel (64 bit)

Note: This only indicates how the developer wrote the code, not that a 64 bit application will run noticeably faster (much else depends on your machine's configuration).

Also, if your favorite application is otherwise Snow Leopard compatible, but has PowerPC as the Kind, it will require Rosetta to run. Rosetta can be installed as part of the Custom Snow Leopard installation, or, if it is not installed, then Snow Leopard will offer to install Rosetta any time you attempt to launch a PowerPC application.


Written by Pendragon with contributions from dianne, joemikeb and macnerd10 in Determining application kind in Mac OS X 10.6.
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