const elt = document.querySelector("#myId p.article > a");

​

//Pretend there is a <p> with class "example"

const myParagraph = document.querySelector('.example');

//You can do many this with is

myParagraph.textContent = 'This is my new text';

var element = document.querySelector("#myid .myclass p");

​

// TO select all the h1 from Html

document.querySelectorAll("h1")

​

//To select h1 from a particular class or id

document.querySelector(".className/#id h1")

<div id="foo\bar"></div>

<div id="foo:bar"></div>

​

<script>

  console.log('#foo\bar');               // "#fooar" (\b is the backspace control character)

  document.querySelector('#foo\bar');    // Does not match anything

​

  console.log('#foo\\bar');              // "#foo\bar"

  console.log('#foo\\\\bar');            // "#foo\\bar"

  document.querySelector('#foo\\\\bar'); // Match the first div

​

  document.querySelector('#foo:bar');    // Does not match anything

  document.querySelector('#foo\\:bar');  // Match the second div

</script>

let Element = document.querySelector(".class");

// Go to html and find out what type of HTML element you want to select. 

// Is it div, p, h3 or something else? 

// When you know, select it with

document.querySelector();

// querySelector() accepts the name of the element as argument

const para = document.querySelectorAll('p');