title: HMAC vs simple MD5 Hash
body: <p>Can anyone point out what the advantage of using <code>HMАC</code> is?</p>
  
  <p>For example, if I have a text <code>T</code> and a key <code>K</code>, I can use either <code>HMAC-MD5</code> algorithm or <code>Md5(T + K)</code> to get a signature. </p>