By Joe Hutsko, Barbara Boyd

Most people lock their cars and house doors when they’re away, and your Mac should be no exception to this practice. To protect your Mac physically, you can get a security cable that wraps around an immovable object (like that heavy roll-top desk you have in the den) and then attaches to your Mac.

You can attach it by threading it through a handle or hole in your Macintosh case, or if you have a MacBook Pro, by connecting it to your Mac’s built-in security slot, which is a tiny slot that a security cable plugs into. If you have a MacBook Air, don’t bother searching because there is no security slot, but Maclocks makes an unobtrusive “security skin.”

Some companies that sell security cables are

Of course, security cables can be cut, although a security cable deters a thief who forgot his bolt cutters.

After protecting your Mac physically, you have other ways to lock down your Mac and keep other people out. Use a password to stop intruders from sneaking into your computer if you step away from your desk, encrypt the files, and use a software or hardware firewall, or both, to stop intruders from sneaking into your computer over the Internet.

Anyone with enough time, determination, and skill can defeat passwords and firewalls. Security can only discourage and delay an intruder, but nothing can ever guarantee to stop one.