The Web browser is probably the single most important tool out there for Web developers, because it establishes how people see everything we build. But what does the browser actually do? We write code, the browser receives our code, and then....? Software engineer Tali Garsiel set out to find how modern browsers work. Using browser source code and published information about their internals, she developed a comprehensive guide to how WebKit and Gecko browsers function. It covers Chrome, Firefox and Safari, which together comprise almost 60 percent of the browser market. Garsiel writes:

Web browsers are probably the most widely used software. In this primer, I will explain how they work behind the scenes. We will see what happens when you type google.com in the address bar until you see the Google page on the browser screen.

This is a soup-to-nuts explanation of exactly what happens from the first byte the browser sees to the last pixel that gets displayed. As a bonus, Garsiel provides tips and links for optimizing client-side performance. Using the browser effectively can be the difference between making our websites and applications great... or just OK How will you use a browser differently, once you know how it works? Tell me by posting a comment below.