# How Browsers Work
AI-readable version of this post.
Path: /frontend/how-browsers-work
Category: Frontend
Date: 2011-08-01
Author: Web Platform
Reading time: 1 min
Description: From response bytes to painted pixels.
## Navigation

The browser resolves DNS, opens transport, streams HTML, and starts parsing before the full response arrives.

## Render tree

DOM and CSSOM combine into a render tree for visible elements. Scripts can block parsing unless deferred.

## Layout paint composite

- Layout computes geometry
- Paint fills pixels
- Composite merges layers

### Performance hint

Prefer transform/opacity animation and profile with real tools instead of guessing.