Reference
Glossary
Every key term used across the five chapters, defined once. Bookmark this page — you'll come back to it during your first few pull requests.
A
- AGENTS.md
- A file giving AI coding agents (like OpenCode) persistent instructions for a repository.
B
- Branch
- A parallel line of work inside a repository; contributions always happen on a branch, never directly on
main.
C
- Clone
- Downloading a repository to your local machine with
git clone. - Commit
- A saved snapshot of changes with a message explaining what and why.
- Code review
- A maintainer's examination of a PR with comments, requests, and approval.
- CI (Continuous Integration)
- Automated checks (tests, linting) that run on every push and must pass before merge.
- Contributor
- Anyone whose work has been merged into a project.
- CONTRIBUTING.md
- The project's rulebook: how to set up, style code, and get changes accepted. Read it before your first PR.
D
- Diff
- The line-by-line comparison of what a PR adds, removes, or changes.
- Draft PR
- A pull request marked 'not ready to merge', used to invite early directional feedback.
F
- Fork
- Your personal copy of someone else's repository, under your account, where you can push changes.
G
- Git
- The version-control system that records changes to files over time; runs on your machine.
- GitHub
- A website that hosts Git repositories and adds collaboration tools: issues, pull requests, reviews, CI.
- good first issue
- A label maintainers use to mark work that is scoped and friendly for newcomers.
I
- Issue
- A tracked conversation about a bug, feature, or task in a repository.
L
- Label
- A tag on issues/PRs (bug, help wanted, good first issue) used for triage and search.
- License
- The legal file (MIT, Apache-2.0, GPL…) defining how the project may be used and distributed.
M
- Merge
- Accepting a PR's changes into the project's main history.
- Maintainer
- A person trusted to review, merge, and steer a project.
- MCP (Model Context Protocol)
- A standard for connecting AI agents to external tools and data sources.
O
- Open source
- Software whose source code is public under a license that allows reading, modifying, and sharing it.
- origin
- The default remote name pointing at your fork — you push here.
P
- Push
- Sending local commits to a remote (your fork) on GitHub.
- Pull Request (PR)
- A request to the project to merge your branch, presented as a diff for review.
- PAT (Personal Access Token)
- A password substitute Git uses to authenticate pushes over HTTPS.
R
- Repository (repo)
- A project's folder on GitHub including its full code history.
- Rebase
- Replaying your commits on top of the latest main to keep history linear.
S
- Squash merge
- Merging strategy that collapses all PR commits into a single commit on main.
- SSH key
- A key pair that authenticates your machine to GitHub without passwords.
U
- upstream
- The conventional remote name for the original project you forked from — you sync from here.
Done with the reference? Back to the story.