Once you've set up more than one account, the dialog box shown in Figure 12-1 appears whenever you turn on the Mac, whenever you choose a→Log Out, or whenever the Mac logs you out automatically (Section 12.11.3). But a few extra controls let you, an administrator, set up either more or less security at the login screen—or, put another way, build in less or more convenience:
Open System Preferences, click Accounts, and then click the Login Options button (Figure 12-11). Here are some of the ways you can shape the login experience for greater security (or greater convenience).
Automatically log in as: This option eliminates the need to sign in at all. It's a time-saving, hassle-free arrangement if only one person uses the Mac, or if one person uses it most of the time.
When you choose an account holder's name from this pop-up menu, you're prompted for his name and password. Type it and click OK.
From now on, the dialog box shown in Figure 12-1 won't appear at all at startup time. After turning on the machine, you, the specified account holder, will zoom straight to your desktop.
Of course, only one lucky person can enjoy this express ticket. Everybody else must still enter their names and passwords. (And how can they, since the Mac rushes right into the Automatic person's account at startup time? Answer: The Automatic thing happens only at startup time. The usual login screen appears whenever the current account holder logs out—by choosing a→Log Out, for example.) ...