jQuery is very useful and easy to learn and it’s very, very powerful. If you look at the code below you’ll see that with a few lines of code we are able to remove duplicate content from the list.

Here is my HTML

<ul >
  <li value="1" name="test" id="test1">test 1<li>
  <li value="1" name="test" id="test3">test 3<li>
  <li value="1" name="test" id="test3">test 3<li>
  <li value="3" name="test" id="test4">test 4<li>
  <li value="4" name="test" id="another1">another 1<li>
  <li value="5" name="test" id="another1">another 2<li>
   <li value="5" name="test" id="another1">another 2<li>
  <li value="4" name="test" id="another3">another 3<li>
</ul>

Here is my CSS

.list {
  
  list-style:none;
}

Here is jQuery

$(document).ready(function(){
  var found = {};
  $('li').each(function(){
    var $this = $(this);
    if(found[$this.attr('value')]){
      $this.remove();
    }else{
      found[$this.attr('value')] = true;
    }
  });
});