add to an html in javascript code example

Example 1: javascript append to paragraph

// In the JS script

var parElement = document.getElementById("myPar");
var textToAdd = document.createTextNode("Text to be added");
parElement.appendChild(textToAdd);

//In the HTML file

<p id="myPar"></p>

Example 2: how to add elements in javascript html

//adding 'p' tag to body

  var tag = document.createElement("p"); // <p></p>
  var text = document.createTextNode("TEST TEXT"); 
  tag.appendChild(text); // <p>TEST TEXT</p>
  var element = document.getElementsByTagName("body")[0];
  element.appendChild(tag); // <body> <p>TEST TEXT</p> </body>