title: Are email addresses allowed to contain non-alphanumeric characters?
body: <p>I'm building a website using Django. The website could have a significant number of users from non-English speaking countries.</p>
  
  <p>I just want to know if there are any technical restrictions on what types of characters an email address could contain.</p>
  
  <p>Are email addresses only allowed to contain English letters, numbers, <code>_</code>, <code>@</code> and <code>.</code>?</p>
  
  <p>Are they allowed to contain non-English alphabets like <code>é</code> or <code>ü</code>?</p>
  
  <p>Are they allowed to contain Chinese or Japanese or other Unicode characters?</p>