title: Is array syntax using square brackets in URL query strings valid?
body: <p>Is it actually safe/valid to use multidimensional array synthax in the URL query string?</p>
  
  <pre><code>http://example.com?abc[]=123&amp;abc[]=456
  </code></pre>
  
  <p>It seems to work in every browser and I always thought it was OK to use, but accodring to a comment in this article it is not: <a href="http://www.456bereastreet.com/archive/201008/what_characters_are_allowed_unencoded_in_query_strings/#comment4" rel="noreferrer">http://www.456bereastreet.com/archive/201008/what_characters_are_allowed_unencoded_in_query_strings/#comment4</a></p>
  
  <p>I would like to hear a second opinion.</p>