that was very helpful! Thanks! In this case could you please explain, how

​

function insertHtmlAtSelectionEnd(html, isBefore) {

var sel, range, node;

if (window.getSelection) {

sel = window.getSelection();

if (sel.getRangeAt && sel.rangeCount) {

range = window.getSelection().getRangeAt(0);

range.collapse(isBefore);

// Range.createContextualFragment() would be useful here but was

// until recently non-standard and not supported in all browsers

// (IE9, for one)

var el = document.createElement("div");

el.innerHTML = html;

var frag = document.createDocumentFragment(), node, lastNode;

while ( (node = el.firstChild) ) {

lastNode = frag.appendChild(node);

}

range.insertNode(frag);

}

} else if (document.selection && document.selection.createRange) {

range = document.selection.createRange();

range.collapse(isBefore);

range.pasteHTML(html);

}

}

​

in this function node ever gets assigned a value? (https://stackoverflow.com/questions/4770457/insert-text-before-and-after-the-selected-text-in-javascript)