I was looking over one source code and that code in many sections there were used this function data-cid and data-cdata. I can't understand this thing. many places I read this is good for a webpage but how and what is it.
<header class="c-global-header has-masthead-bg" **data-cid="site/global_header-1569581428_9578_308"** role="banner" data-analytics-placement="navigation" style="background-image:url()" **data-cdata="{}"**>
