Web browsers are ubiquitous, but how do they work? This book explains, building a basic but complete web browser, from networking to JavaScript, in a couple thousand lines of Python.

Follow this book’s blog or Twitter for updates. You can also talk about the book with others in our discussion forum.

If you are enjoying the book, consider supporting us on Patreon.

Or just send us an email!

Part 1: Drawing Graphics

1. Downloading Web Pages
   URLs and HTTP requests
2. Drawing to the Screen
   Creating windows and drawing to a canvas
3. Formatting Text
   Word wrapping and line spacing

Part 2: Viewing Documents

4. Constructing a Document Tree
   Parsing and fixing HTML
5. Laying Out Pages
   Inline and block layout, plus the box model
6. Applying User Styles
   Parsing and applying CSS
7. Handling Buttons and Links
   Hyperlinks and browser chrome

Part 3: Running Applications

8. Sending Information to Servers
   Form submission and web servers
9. Running Interactive Scripts
   Changing the DOM and reacting to events
10. Keeping Data Private
    Cookies and logins, XSS and CSRF

Part 4: Modern Browsers

11. Adding Visual Effects
    Blending, clipping, and compositing
12. Scheduling Tasks and Threads
    The event loop and the rendering pipeline
13. Animating and Compositing
    Smooth animations using the GPU
14. Making Content Accessible
    Keyboard input, zooming, and the accessibility tree
15. Supporting Embedded Content
    Images and iframes