How to read this site

This site has a lot of small visual grammar: bespoke callouts, API pills, version badges, source superscripts, uncertainty markers. It is worth two minutes to learn it, because the grammar is carrying information you will otherwise miss.

TL;DR#

Pages follow a fixed order: TL;DR, mental model, big picture, deep dive, evolution, source, curiosity, hands-on, quiz, sources. You can jump straight to what you need.
Coloured pills are API levels: API 33 · Android 13. Hover or tap to confirm the mapping.
Superscript numbers are citations. They jump to the numbered source list at the bottom.
Dotted underlines are glossary terms: tap for a definition without leaving the page.
Dashed underlines with an "unverified" tag mean we could not confirm the claim against a primary source, and we are telling you so.

Mental model#

Reading a technical site is like reading a map legend before walking. The legend is dull, but without it you will misread the map: a red line might be a motorway or a border, and a small icon might be a viewpoint or a hazard.

This page is the legend.

Where the analogy breaks#

Legends are usually complete. This one is not: the content of the site will keep introducing new marks as it grows. If something looks like a badge and is not explained here, it is probably a one-off and the surrounding text should say what it means.

The big picture#

Loading diagram…

Text description of this diagram

A treemap of the software on an Android phone. The open AOSP platform is the largest area, followed by the vendor and OEM code, then Google's proprietary services, then the apps a user installs. The diagram is a reminder that when this site says 'Android', it is usually referring to the open platform layer, not to any particular phone.

Deep dive#

The page anatomy#

Every topic page uses the same sections, in the same order:

Section	What it is for
TL;DR	Three to five bullets. If you read nothing else.
Mental model	An everyday analogy, then an honest note about where it breaks.
The big picture	At least one interactive diagram.
Deep dive	The real mechanics, with code and AOSP paths.
How it evolved	A version table, generated from data.
Under the hood	Direct links into the source.
Curiosity corner	Two to five facts that make the mechanism memorable.
Try it	Commands you can run on a real device.
Build it	A matching project, if there is one.
Check yourself	A quiz drawn from the page.
Sources	The numbered list, always at the bottom.

The badges#

API 36Android 16 is an API pill: it tells you the level a feature arrived at. Framework is a layer badge: it tells you which part of the stack a thing belongs to. The level badge under a page title (beginner, intermediate, nerd) is a difficulty hint, not a prerequisite.

The citation system#

Every numbered superscript — ¹ — links to a numbered entry in the Sources section. The numbers are assigned by first appearance on the page, so they are stable and you can jump back and forth. Every page lists the date its facts were last checked.

The uncertainty marker#

This is the most important piece of grammar on the site. Some claims are true but hard to trace to a primary source.unverified(illustrative example) When we cannot confirm something, we say so inline rather than quietly dropping it or quietly believing it. The full policy is on How we know.

The interactive diagrams#

Figures with a player have keyboard controls: arrow keys step, space plays or pauses, and the scrubber jumps. Every diagram has a text description in a collapsible section underneath, for screen readers and for anyone who prefers words. Every diagram also works at 360 pixels wide.

How it evolved#

The site's own conventions have a source too: the citation and uncertainty system is modelled on scientific publishing, the interactive format on explorable explanations, and the version table on the way Android's own release notes document behaviour changes.

ancient →ProseThe baseline: text with references.

1990s →HypertextLinks turn a bibliography into a network.

2010s →ExplorablesInteraction turns a diagram into an experiment.

2026 →This siteData-driven facts, interactive mechanisms, visible uncertainty.

Curiosity corner#

Every page has a verification date because Android changes annually. A page without one is a page you cannot trust.
The quizzes are generated from the same data as the pages, so an answer cannot drift away from the prose without the build failing.

Why is the site called Zygote?Because the zygote is the one process every app descends from — a single point where the whole platform meets the code you write. …Open card →

Try it#

There is nothing to run for this page. The first lab — Lab 0, setup — will get a device or emulator ready for everything that follows.