Атрибут data-*

https://yocton.ru/html-elements/global-attributes/data

by yocton

HTML

<!DOCTYPE html>
<html lang="ru">
  <head>
    <meta charset="utf-8">
    <title>data-*</title>
  </head>
  <body>
    <div id="page" data-page-id="1234567890" class="page" data-page-lang="ru">Страница</div>
    <div id="info">инфо о странице</div>
  </body>
</html>

JavaScript

page.onclick = function() {
   let text = `id=${this.dataset.pageId}
     lang=${this.dataset.pageLang}`;
   document.getElementById('info').innerHTML = text;
 }