title: npm install vs. edit package.json and npm update
body: <p>Curious what is the difference between the two procedures:</p>
  
  <ol>
  <li><code>npm install xyz</code></li>
  <li>edit <code>package.json</code>, adding required module names like this:</li>
  </ol>
  
  <hr>
  
  <pre><code>"dependencies": {
      "express": "~3.4.4",
      "mongodb": "*",
      "body-parser": "*",
      "bson": "*"
    },
  </code></pre>
  
  <p>and then <code>npm update</code></p>