Mac OS X - How to Determine If an Application is Running in Classic or Native Mode

The following are some indications you can look for to tell what mode the application is running in:

Classic Mode Applications

• The Apple menu in the left-hand corner will be multicolored.
• The name or icon of the application will appear in the upper right-hand corner of the menu bar.
• Windows for classic applications will have the a close box in the upper left-hand corner and a window shade and resize box in the right-hand corner.

Native Applications

• The Apple menu in the left-hand corner will be blue.
• Windows will have three colored "stones" (red, yellow, and green) in the upper left-hand corner.