Can other people on my WiFi network access the documents on the hard drive attached to my AirPort Extreme?

 No, can not be possible for  other people on my WiFi network access the documents on the hard drive attached to my AirPort Extreme:

• You can connect to the network drive with your Mac. Because the Finder sees your AirPort Extreme as a server, the network drive appears differently from other mounted hard discs, but don't worry: you can use it just like any other hard disc.
• Toggle over to the Finder.
• Select Preferences from the Finder menu. The Finder Preferences window appears .
• If it isn't already checked, choose the Connected servers checkbox.
• Close the Preferences window in Finder.
• Open a new Finder window. (You may do this by going to the File menu and selecting New Finder Window.) A window similar appears
• Select the AirPort Extreme Base Station from the Finder window's sidebar. In the Finder window, the hard drive shows as a folder.

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