What's the first event fired when a web page is loaded to the browser

Question

As asked in the title, what's the first event fired when a web page is loaded to the browser? I believe there are events before window.onload. What are they, and which one is the first fired?

Answer 1

If you're looking to invoke an event handler before onload, DOMContentLoaded is one event that usually fires before.

document.addEventListener('DOMContentLoaded', functionRef, false);