title: In what cases an HTTP request is made but no response is received?
body: <p>I am using axios to make an HTTP request and getting an error. This is a <a href="https://github.com/axios/axios#handling-errors" rel="nofollow noreferrer">snippet from axios docs</a> talking about handling of errors.</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>axios.get('/user/12345')
    .catch(function (error) {
      if (error.response) {
        // The request was made and the server responded with a status code
        // that falls out of the range of 2xx
        console.log(error.response.data);
        console.log(error.response.status);
        console.log(error.response.headers);
      } else if (error.request) {
        // The request was made but no response was received
        // `error.request` is an instance of XMLHttpRequest in the browser and an instance of
        // http.ClientRequest in node.js
        console.log(error.request);
      } else {
        // Something happened in setting up the request that triggered an Error
        console.log('Error', error.message);
      }
      console.log(error.config);
    });</code></pre>
  </div>
  </div>
  </p>
  
  <p>In my case, <code>error.request</code> is coming out to be true, which means (according to the docs) a request was made but no response was received. My question is, what could be causing it? what are the cases when a request is made but no response is received?</p>
  
  <p>Thanks</p>