window.onload vs document.onload

window.onload

• It is fired when the entire page loads, including its content (images, css, scripts, etc.)
• $(window).load()

document.onload

• It is fired when the DOM is ready which can be prior to images and other external content is loaded
• In general, document.onload event is fired before the window.onload
• $(document).ready()

Also Read:

1. A simple requestAnimationFrame example visually explained
2. window vs document
3. Getting started with localStorage vs sessionStorage in html5
4. pseudo elements vs pseudo classes
5. Applying floats and clearfix to block elements