title: Do I need MD5 as a companion to SHA-1?
body: <p>Do I need <strong>both</strong> MD5 and SHA-1 values to be sure the downloaded file is</p>
  
  <p>a) Untouched by hackers. For example, when I need to download some app's <code>.iso</code> via torrents</p>
  
  <p>and</p>
  
  <p>b) Not corrupted during technical issues? For example, some unstable network connection during download.</p>
  
  <p>Or, probably, SHA-1 value will be enough for both checks?</p>
  
  <p>Also, is SHA-1 (without MD5) enough to be sure that some file downloaded years ago and stored somewhere on my HDD haven't <a href="https://en.wikipedia.org/wiki/Data_degradation" rel="nofollow noreferrer">degradated</a>?</p>