create html element in javascript in a specific div code example

Example 1: add element to body javascript

var elem = document.createElement('div');
elem.style.cssText = 'position:absolute;width:100%;height:100%;opacity:0.3;z-index:100;background:#000';
document.body.appendChild(elem);

Example 2: javascript document.createElement add function

var newTH = document.createElement('th');
newTH.innerHTML = 'Hello, World!';
newTH.onclick = function () {
    this.parentElement.removeChild(this);
};

var table = document.getElementById('content');
table.appendChild(newTH);