Move 3A of 4 · about 8 minutes
STEP 3A — LEARN HOW BROWSERS WORK
Before you choose or tune anything, understand the machine. Five short sub-steps, one idea each. By the end you will know what really happens when you press Enter.
Picture the Job: Request, Receive, Render
Type an address and press Enter. Your browser first asks the Domain Name System (DNS) to turn the name into a numeric IP address. Think of it as looking up a phone number.
Next, it opens a secure connection using HTTPS, the encrypted version of the HTTP protocol. The padlock icon simply tells you this connection is encrypted, not that the site is trustworthy.
Then the server sends back files: HTML for structure, CSS for style and JavaScript for behaviour. Your browser reads the HTML and builds a tree of everything on the page, called the Document Object Model, or DOM.
Finally, it works out where every box goes (layout) and colours in the pixels (paint). All of this usually happens in well under a second. Hold on to this sequence; every later move builds on it.
Meet the Three Engines
Now look beneath the logo. The rendering engine does the heavy lifting from sub-step 1. Only three are in wide use.
Blink
Built by Google and used by Chrome, Microsoft Edge, Opera, Brave, Vivaldi and Samsung Internet. Paired with the V8 JavaScript engine.
Gecko
Built by Mozilla for Firefox and also used by Tor Browser. Paired with the SpiderMonkey JavaScript engine.
WebKit
Maintained largely by Apple for Safari. Paired with JavaScriptCore. On iPhone and iPad, Apple long required every browser to use WebKit; EU rules under the Digital Markets Act loosened this in 2024.
Take one lesson from this: when people say there are dozens of browsers, there are really three engines wearing many outfits.
Walk Through the Rumble
History explains today's line-up. Read this timeline once, slowly.
1990 — The first browser
Tim Berners-Lee writes WorldWideWeb at CERN.
1993–1994 — Mosaic and Netscape
Mosaic brings images inline; Netscape Navigator turns browsing into a business.
1995–2001 — The first browser war
Internet Explorer, bundled with Windows, overtakes Netscape. The US antitrust case against Microsoft follows.
2003–2004 — New challengers
Apple launches Safari; Mozilla, born from Netscape's open-sourced code, ships Firefox 1.0.
2008–2013 — Chrome arrives
Google releases Chrome, then forks WebKit into Blink. Opera switches to Blink the same year.
2020 — Edge rebuilt
Microsoft relaunches Edge on Chromium, ending its own EdgeHTML engine.
Notice the pattern: each "war" was about defaults. Whoever ships the browser people don't change wins the rumble.
Know Who Writes the Rules
Browsers don't invent the web alone. Learn the four referees.
The WHATWG maintains the HTML Living Standard and the DOM standard, a role the W3C formally recognised in 2019. The W3C still publishes many other specifications, including CSS and accessibility guidelines such as WCAG. Ecma International's TC39 committee evolves JavaScript under the name ECMAScript. The IETF looks after the network protocols, including HTTP and TLS.
Why should a beginner care? Because when a site "only works in Chrome", the cause is usually a feature that has not landed in every engine yet, not a broken browser.
Try It Yourself
Reading is good; doing is better. Open any page and press F12 (or Cmd+Option+I on a Mac) to open the developer tools.
Click the Network tab and reload. Watch every file arrive, one line per request. You are seeing sub-step 1 live.
Then find out exactly what you are running. Type chrome://version in Chrome or Edge, about:support in Firefox, or open Safari's About window. Note your engine and version number. You will use it in the next move.
Your Next Move
You know the engine. Now compare the cars built on top of it.
Go to Step 3B