On the Macintosh: Extensions Off
In times of troubleshooting, you wouldn’t get far without some means of starting a computer from Ground Zero, its native, virginal, factory-fresh state, free from any software you’ve added to its operating system. In Windows, this condition is known as Safe Mode.
On the Macintosh, restoring the OS to its bare minimum components is called booting with extensions off. To do so, restart the computer while pressing the Shift key. When you see the words “Extensions off” or “Extensions disabled” on the screen, you can release the Shift key; the Macintosh is now running without any system add-ons, such as extensions, control panels, startup items, and so on.
Without these helpers, the Macintosh can’t read CD-ROMs, go online, send faxes, connect to networks, and so on. On the other hand, the computer should start up especially quickly and run exceptionally smoothly. The troubleshooting work is halfway done: having determined that whatever problem you’re having is a result of corrupted or conflicting extensions, you can now begin the business of determining which ones are causing the problem. For details on this process, see the sidebar “Mastering the Extensions Manager” in Troubleshooting.
On the Macintosh: Saving Files
You save documents on the Macintosh exactly the way you do in Windows: by choosing File → Save or by pressing, in the Macintosh case, Command-S.
Only a few differences are worth noting:
When saving a document for ...