FileVault Preference Pane Click to see a larger image

For the most security for your user account, you need to use FileVault. FileVault not only password protects your account, it also encrypts it. Account passwords can be discovered and changed, but an account encrypted with FileVault cannot be accessed without its password.

To set your user account to use FileVault:

1. Go to System Preferences from the Dock or the Apple Menu.
2. Optionally set a Master Password for your computer. (see more below)
3. Go to the File Vault tab.
4. Click "Turn on FileVault..."

WARNING: Once you encrypt your user account with FileVault, you must remember the password because it is the unique key that will decrypt your account. No tool can decrypt the account besides the password.

SAFETY NET: Setting a Master Password for your computer gives you a safety net against forgotten File Vault (and regular account) passwords. The Master Password can be used to log into all accounts on the Mac. This reduces the security of all accounts, but could be an acceptable trade off against forgotten passwords.

NOTE: File Vault only encrypts files in your user folder. Files at the root of the internal hard drive or on external hard drives are not encrypted.

Related Items: User Account | Security | Password