Does the browser start rendering HTML when the first data packet is recieved

Tuesday, July 8, 2014

In a web browser (mobile if that matters), I assume that when you access a webpage a number of packets of HTML data are returned. If that is correct, do web browsers begin rendering the HTML before all of the HTML packets have been returned?

I ask this because I'm writing a webpage and I've heard that above the fold content should have lower latency than below the fold content and I was wondering why this would matter if the browser waits for the entire HTML response before processing.