Docs: kdf example with VeraCrypt volume header keys
//! stretching.
//!
//! An example of this could be deriving a key from a user-submitted password and using this derived key
-//! for disk encryption.
+//! in disk encryption. The disk encryption software VeraCrypt, [uses](https://www.veracrypt.fr/en/Header%20Key%20Derivation.html)
+//! PBKDF2-HMAC-SHA512 to derive header keys, which in turn are used to encrypt/decrypt the master keys responsible for encrypting
+//! the data in a VeraCrypt volume.
+//!
//!
//! # About:
//! - Uses PBKDF2-HMAC-SHA512.
