What is the difference between FileVault 2 and Disk Utility Encryption?
Solution 1:
Both, do the same thing, that is to encrypt your hard drive. However, the difference is in the approach and can be disastrous if you’re not careful with it.
Point 1:
When you use the Disc Utility to create an HD with Mac OS Extended (journaled, encrypted) - it will “Format” the drive (any data that you have on it will be lost, forever), it will then ask you set up a password. Once you’ve provided the info, and click Ok. It will format the hard drive within minutes (depending on the disk size of course). This is faster, but a destructive process.
When you use FileVault - it encrypts the hard drive while maintaining the data within it. This is a slow and reversible (i.e. You can turn FileVault ON/OFF as you choose) process, often takes a few hours. But, if you need to preserve the data on the HD, then this is the way to go.
Point 2:
FileVault can be enabled in System Preferences > Security & Privacy > FileVault to encrypt the existing data on the internal HDD on a Mac.
Disk Utility > Erase can be used to format an existing or new partition and encrypt the volume as Mac OS Extended (Journaled, Encrypted).
Conclusion:
If you’re concerned about the privacy of your files and user data, and your computer contains information that shouldn’t be seen without authorized access, you should absolutely use FileVault disk encryption.