Location Services means “knowing where I am.” It’s the feature that lets your laptop figure out its own time zone automatically, for example, or that lets a weather Web site show your local weather the first time you visit.

Every time a program wants to use your current location for its own features, you’ll be asked about it. (The Mac figures out your location based on its proximity to known WiFi networks.) Each time you say OK, the program that did the asking installs its own name into the list here.

You can turn off the checkboxes of the programs you’d rather didn’t know where you are, or you can turn off location tracking altogether by turning off the “Enable location services” box.

Some programs work better if you allow them to access your database of names and addresses. For example, Skype wants access so that it can incorporate your address book into its address book. This list shows all of the programs that access your Contacts—and offers checkboxes to turn off that access.

Here, you’ll see programs that want to access your Twitter and Facebook accounts. Once again, you can turn off their access, if you like.

If you turn on this box, your Mac will automatically and quietly send data to Apple about what’s going on with your Mac (anonymously, of course—Apple won’t know it’s you). The transmissions include details about crashes and freezes, what programs and hardware you use, what software versions and peripherals you have, and so on.

None of this is transmitted unless you turn this box on.

Incidentally, you have another chance to turn on automatic reporting: when a program, or your Mac, crashes. At that time, a message invites you to send a crash report to Apple; you can click either OK or No Thanks. You can also turn on “Don’t ask me again,” which makes your OK or No Thanks decision permanent. (What you’re actually doing with that “Don’t ask me again” option, of course, is changing the status of this checkbox here in the Security & Privacy pane of System Preferences. That’s how you can change your mind later.