In Mac OS and Mac OS X, what does the startup icon mean?

When you start your Mac OS or Mac OS X computer, you'll see an icon telling you whether the operation was successful. Here's what each of the possible icons mean:

• The icon of a disk with a question mark means the computer is waiting for you to insert a startup disk. It may also mean that the computer doesn't recognize your internal hard drive as a valid startup disk.
  
  
• The icon with a large "X" means that the computer ejected an invalid startup disk and is expecting you to insert a valid startup disk.
  
  
• The Sad Mac frowning face icon means there is a problem with either the system software or the computer. On newer Mac OS computers, this will be accompanied by various tones to help diagnose the cause of the problem. For older computers, RAM problems will be indicated by an address beneath the icon, which indicates where the problem was found.
  
  
• The flashing globe icon means you are trying to start from a netboot server that doesn't exist or is offline.
  
  
• The Happy Mac smiling face or gray apple means that no problems were detected, and the system will continue to boot normally.

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