In Mac OS X, how do I set the clock and time zone?

Mac OS X and many of its applications depend on accurate clock and time zone settings. To set the clock and time zone:

1. From the Apple menu, open System Preferences....
2. Click the Date & Time icon, or open the View menu and click Date & Time. If the padlock at the bottom of the window is closed, click it and enter an administrator name and password. Select the Date & Time tab, if it isn't already selected.
3. Select Set date & time automatically: to set your date and time according to one of Apple's Network Time Protocol (NTP) servers.
4. Select the Time Zone tab. If the system is unable to determine your location automatically, uncheck Set time zone automatically using current location so you can manually set your location. On the world map, select your time zone region. From the "Closest City:" drop-down list, choose Indianapolis for Eastern Time or Chicago for Central Time.