title: How can I delete special characters?
body: <p>I'm practicing with Ruby and regex to delete certain unwanted characters. For example:</p>
  
  <pre><code>input = input.gsub(/&lt;\/?[^&gt;]*&gt;/, '')
  </code></pre>
  
  <p>and for special characters, example &#9787; or &#153;:</p>
  
  <pre><code>input = input.gsub('&amp;#', '')
  </code></pre>
  
  <p>This leaves only numbers, ok. But this only works if the user enters a special character as a code, like this:</p>
  
  <pre><code>&amp;#153;
  </code></pre>
  
  <p><strong>My question:</strong>
  How I can delete special characters if the user enters a special character without code, like this:</p>
  
  <pre><code>™ ☻
  </code></pre>