selectors : single selector and multi selectors

 single selector:

  document.getElementById

        let a=document.getElementById('div1');

console.log(a);

let element=a.className;

console.log(element);

a.innerHTML='what is your'

a.style.backgroundColor = "red";

a.innerHTML='<b>click here</b>'

multiple selector: Select multiple query or class using 

  1. getElementsByClassName

                        let elems=document.getElementsByClassName('div1')

Array.from(elems).forEach(function(argument){

console.log(argument);

argument.style.backgroundColor = "red";

argument.style.color = "white";

})