<script src="https://cdn.ckeditor.com/ckeditor5/23.1.0/classic/ckeditor.js"></script> in html5 code example
Example 1: cdn ckeditor
<script src="https://cdn.ckeditor.com/4.14.0/standard/ckeditor.js"></script>
Example 2: ckeditor cdn
<script src="https://cdn.ckeditor.com/ckeditor5/23.1.0/classic/ckeditor.js"></script>