Element.appendChild()
Insert an element at the end of a set of elements inside a shared parent. Call the appendChild() method on the reference node, and pass in the new node as an argument.
// Create a new element
var newNode = document.createElement('div');
// Get the reference node
var referenceNode = document.querySelector('#some-element');
// Insert the new node after the last element in the parent node
referenceNode.appendChild(newNode);