> Disk encryption prevents revealing the plaintext of files on disk, but you can still observe their ciphertext changing when the file changes. File encryption

> Disk encryption prevents revealing the plaintext of files on disk, but you can still observe their ciphertext changing when the file changes. File encryption does that. Disk encryption means that you don't even know how many files there are, much less which ones were changed. The whole disk is just a blob of random data until the right password is entered.