GitHub Actions is GitHub's built-in CI/CD platform. It automates build, test and deployment workflows directly inside GitHub repositories. Traditional tools such as Jenkins or TeamCity need separate infrastructure that you install and run, while Actions is hosted and part of GitHub itself.
The main differences:
It is integrated with repositories, pull requests and issues, so check results show on each commit and pull request.
It is event-driven, so pushes, pull requests and releases trigger workflows directly.
A large Marketplace offers pre-built actions to reuse instead of writing scripts.
Workflows are YAML files stored in .github/workflows/, versioned with the code.
GitHub-hosted runners execute the jobs, so there are no build servers to manage.
Rewriting in plainer words…
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