FileVault drive encryption is a service offered for Apple/Mac operating systems. It allows users to encrypt data on their hard drives. If you use FileVault, your data will be secure, even if your computer is misplaced.
When FileVault is turned on, the data on your computer's hard drive can't be read without a secret FileVault password, even if the hard drive is placed into a different computer.
ITS is starting to encrypt laptop hard drives. Initially the process will be offered on an opt-in basis but soon laptops will come with their hard drives encrypted by default.