Note: For information about Location Services in OS X Lion and Safari 5.1 or later, see this article. For information about Location Services on an iPhone or iPod touch, see this article.
Location Services in Mac OS X v10.6
In Mac OS X v10.6, Location Services can be used for setting the time zone automatically in the Date & Time System Preferences.

Location Services in Safari 5
When you visit a geolocation-enabled website in Safari 5, you are asked if you want to share your location with the website. Such websites may give you helpful location information, such as showing you the nearest post office or ATM. In the dialog sheet, you can check "Request permission only once every 24 hours" to allow your authorization to last for up to 24 hours.

Note: You can reset all website authorizations in Safari 5 by choosing Reset Safari from the Safari menu, then enabling "Reset all location warnings" checkbox (don't select the other checkboxes unless you are sure you want to reset those as well).
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Important: The data collected to provide your location does not identify you personally. If you do not want such data collected, you can choose to disable the feature, which does not negatively affect your Mac in any way.
Disabling location services
If you want to disable Location Services features in Safari 5 only (Mac OS X v10.5, 10.6, or Microsoft Windows):
- With Safari running, choose Preferences from the Safari menu.
- Click the Security tab.
- Deselect the "Allow websites to ask for location information" checkbox.
If you want to disable Location Services in Mac OS X v10.6:
- From the Apple menu, choose System Preferences.
- From the View menu, choose Security.
- Click the General tab.
- If the icon in the lower-left corner is locked, click it to authenticate with your admin password (to unlock the Security pane).
- Click the "Disable Location Services" checkbox.