Creating & removing HTML Elements (Nodes)

Creating:

<div id="div1">
<p id="p1">This is a paragraph.</p>
<p id="p2">This is another paragraph.</p>
</div>

<script>
var para = document.createElement("p");
var node = document.createTextNode("This is new.");
para.appendChild(node);

var element = document.getElementById("div1");
element.appendChild(para);
</script>

<div id="div1">
<p id="p1">This is a paragraph.</p>
<p id="p2">This is another paragraph.</p>
</div>

<script>
var para = document.createElement("p");
var node = document.createTextNode("This is new.");
para.appendChild(node);

var element = document.getElementById("div1");
var child = document.getElementById("p1");
element.insertBefore(para, child);
</script>

// Doesn't work in IE
<div id="div1">
<p id="p1">This is a paragraph.</p>
<p id="p2">This is another paragraph.</p>
</div>

<script>
var parent = document.getElementById("div1");
var child = document.getElementById("p1");
parent.removeChild(child);
</script>

<div id="div1">
<p id="p1">This is a paragraph.</p>
<p id="p2">This is another paragraph.</p>
</div>

<script>
var para = document.createElement("p");
var node = document.createTextNode("This is new.");
para.appendChild(node);

var parent = document.getElementById("div1");
var child = document.getElementById("p1");
parent.replaceChild(para, child);
</script>

Removing:

<!--Sample HTML code-->

<div id="top">
  <div id="nested"></div>
</div>

// Removing a specified element when knowing its parent node
var d = document.getElementById("top");
var d_nested = document.getElementById("nested");
var throwawayNode = d.removeChild(d_nested);

// Removing a specified element without having to specify its parent node
var node = document.getElementById("nested");
if (node.parentNode) {
  node.parentNode.removeChild(node);
}

// Removing all children from an element
var element = document.getElementById("top");
while (element.firstChild) {
  element.removeChild(element.firstChild);
}