# alex/what-happens-when

An attempt to answer the age old interview question "What happens when you type google.com into your browser and press enter?"

Repository: https://github.com/alex/what-happens-when
Canonical: https://ross.abutalabs.com/products/what-happens-when
License Family: other
Last push: 2024-08-19T13:02:25+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 4682, "days_push": 744, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 43300, forks 5742 (observed 2026-08-28T04:12:09.025954+00:00)

## What it is
A collaboratively written, deeply detailed answer to the classic interview question 'What happens when you type google.com into your browser and press enter?'. It walks through every layer, from keyboard hardware and USB signaling to OS interrupts, DNS, TCP, TLS, HTTP, and browser rendering.

## Use cases
- prepare for systems engineering interview questions
- learn how the web stack works end to end
- understand what happens between pressing a key and a page loading
- study DNS resolution and TCP/TLS handshakes in depth
- teach networking fundamentals with a concrete example

## When to choose
- you want an exhaustive, layer-by-layer explanation of a URL load
- you are preparing for technical interviews covering networking and OS fundamentals
- you want a community-maintained reference to contribute to or translate

## When to avoid
- you need runnable code or a software tool rather than prose
- you want a short, high-level overview instead of extreme detail
- you need formally reviewed or versioned technical documentation

## Facets
- artifact type: learning-resource
- maturity: active
- function: documentation, developer-tools
- domain: networking, developer-tools, operating-systems, web-development, tutorials
- platform: cross-platform
- tags: interview-preparation, educational, computer-fundamentals, dns, http, collaborative-document

## Member repositories
- alex/what-happens-when (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:12:09.025954+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T16:22:26.713051+00:00, confidence not recorded.
  - readme: https://github.com/alex/what-happens-when (fetched 2026-08-28T04:12:09.025954+00:00, sha 2bb553b48213)
- Data as of 2026-08-30T08:39:29.467469+00:00.