# What GitHub Actions Does — GitHub Actions

Source: https://www.skillbyai.com/en/github-actions/i-what

> CI/CD and automation from events.

## Events trigger workflows

**GitHub Actions** runs automation defined in YAML **workflows** stored in `.github/workflows/`. Workflows are triggered by **events** (a push, a pull request, a schedule, a manual dispatch, an issue being opened, a release) and run **jobs** on **runners**. Common uses: continuous integration (build, lint, test on every pull request), continuous delivery (publish packages, deploy to environments), and repository automation (labelling, stale issue handling, dependency updates). Thousands of reusable **actions** from the Marketplace provide building blocks.

## Automation that lives with your code

Workflows in your repository run jobs on runners when events happen.

![Three ideas: what Actions is, workflow anatomy, runners.](assets/figures/github-actions/section-1-map.svg) — Figure 1.1 — Actions, workflows and runners.

## A kitchen with recipes on the wall

When an order arrives (an event), the cooks (runners) follow the posted recipe (workflow) step by step; the recipe is versioned with the menu (your code).

## Start with CI on pull requests

Running tests on every pull request is the highest-value first workflow for most repositories.

**Quiz:** Where are GitHub Actions workflows stored?

- [ ] Only in organisation settings
- [ ] In the repository wiki
- [x] In .github/workflows/ in the repository
- [ ] In package.json

*Answer:* In .github/workflows/ in the repository. Workflows are versioned with the code.