Data Security: Why you should enable File Vault and protect your data
File Vault, which encrypts your main drive against determined attack, is so transparent that you really do not know it is working. It is a precaution any Mac user should take.
Simply protecting your computer with a password is merely the first step. It’s sensible, and recommended, but it will not stop a determined thief. All that is necessary is to remove the drive from the computer and access it independently. All your data is then laid out for prying eyes to devour.
File Vault effectively prevents this happening. Once turned on, it will work in the background and ensure that everything on your computer is safe.
The latest version, File Vault 2, offers full-disk encryption and, when the computer is powered off, the drive’s data is fully unrecoverable without a password. As a bonus, it will also let you use Find My Mac to completely wipe your drive remotely.