title: When deriving a encryption/decryption key from a passphrase, what encoding is the most commonly used?
body: <p>When I'm deriving an encryption key from a passphrase, it is quite common to use a hash algorithm to derive the key from the passphrase. Examples are SHA-256 (single or multiple rounds) and SCrypt.</p>
  
  <p>But, when entering the passphrase in the hash function, is it usually encoded using UTF-8 or UTF-16?</p>
  
  <p>I know it's impossible to be "compliant" with all other existing encryption mechanisms, but I'd like to know what way is in fact the most common.</p>