data attribute html

<!-- data-* attritubes can be used on any html element -->
<div data-my-custom-data="true"></div>

//javascript get html data attribute
<button data-id="1" >Click</button>
<button data-id="2" >Click</button>
<button data-id="3" >Click</button>
const btns=document.querySelectorAll('button[data-id]');
[...btns].forEach(btn => console.log(btn.getAttribute('data-id')))

var element = document.querySelector('.element');
var dataAttribute = element.getAttribute('data-name');
// replace "data-name" with your data attribute name

console.log(dataAttribute);

const article = document.querySelector('#electric-cars');
 
article.dataset.columns // "3"
article.dataset.indexNumber // "12314"
article.dataset.parent // "cars"

 <p title="I'm a tooltip">This is a paragraph.</p>
 

<a data-color="blue">
  	This tag contains a user-defined color attribute
</a>

<div data-link="https://github.com/k-vernooy">
	This tag contains a data attribute with a link
</div>