title: NVD JSON feeds, tags meaning and their purpose
body: <p>I started moving on from NVD XML feeds to JSON feeds (as XML will no longer be supported from October 2019). Now I am having difficulty understanding the tags and their purpose for use.</p>
  
  <p>For example:</p>
  
  <ol>
  <li><p>What purpose does "operator" tag inside "configuration" have?</p></li>
  <li><p>"affects" tag list out all the vulnerable libraries associated to that CVE-ID, then what is the use of "configuration" tag? Because the information specified inside them just seems a repeat from affects tag except the cpeId which could have also been specified inside the affects tag.</p></li>
  </ol>
  
  <p>I tried searching the NVD website for any such related document but could not find any. 
  The JSON schema does not mention the details or purpose (as expected).</p>
  
  <p>Please point out if any document is created about it. </p>