Git Terminology

Understanding Git terminology is crucial for effectively using Git. Here’s a breakdown of key terms:

Core Concepts

  • Repository (Repo): A directory containing your project and all of its version history. Git stores this history in a hidden .git folder inside the repository. Think of the repository as the entire project, including its past, present, and future.
  • Working Directory/Working Tree: The directory on your computer where you directly edit files. This is where you make changes before adding them to Git’s tracking.
  • Staging Area (Index): A “draft space” where you prepare changes before committing them. You selectively add changes from your working directory to the staging area, and then commit only those staged changes. This gives you fine-grained control over what goes into each commit.
  • Commit: A snapshot of your project at a specific point in time. Each commit has a unique ID (a SHA-1 hash), a message describing the changes, an author, and a timestamp. Commits are the fundamental building blocks of Git’s history.
  • Branch: A named, independent line of development. The default branch is usually called main (or sometimes master). Branches allow you to work on new features, bug fixes, or experiments without affecting the main codebase. Think of branches as parallel universes for your project.
  • Merge: The process of combining changes from one branch into another (e.g., merging a feature branch into the main branch).
  • HEAD: A pointer to the currently checked-out commit or branch. It represents your current working state.

Remote Repositories and Collaboration

Rebase

  • Rebasing in Git takes your changes and reapplies them on top of the latest version of the branch, like stacking fresh edits on a new copy. This keeps the history clean instead of mixing old and new changes together.

Remote Repository

  • A version of your repository stored on another server, like GitHub or GitLab. This allows you to share your work and collaborate. (The GitHub Section outlines this further)

  • Remote Repository: A version of your repository hosted on a server (like GitHub, GitLab, Bitbucket, or a private server). Remotes allow you to collaborate with others and back up your work.
  • Clone: Creating a local copy of a remote repository. This downloads the entire project history to your computer.
  • Push: Uploading your local commits to a remote repository. This shares your changes with others.
  • Pull: Downloading changes from a remote repository to your local repository and merging them into your current branch. This keeps your local copy up-to-date with the remote.
  • Fetch: Downloading changes from a remote repository to your local repository, without merging them into your current branch. This allows you to see what’s changed on the remote before integrating those changes.

Other Important Terms

  • Conflict: Occurs when two different branches have made changes to the same part of the same file. Git cannot automatically merge these changes; you must manually resolve the conflict by choosing which changes to keep (or creating a new, combined version).
  • .gitignore: A file that tells Git which files or directories to ignore. You typically use this to exclude build artifacts, temporary files, and sensitive information (like API keys) from being tracked by Git.
  • Tag: A specific point in Git history, typically used to mark release versions (e.g., v1.0.0, v1.1.0). Tags are like permanent labels on commits.
  • Fork: A copy of a repository (usually on a remote like GitHub). Forks allow you to experiment with changes without affecting the original project. You can then propose changes from your fork back to the original repository using a pull request.

Git Structure and Workflow

Git’s workflow revolves around these four areas:

  1. Working Directory: Your local files, where you make changes.
  2. Staging Area (Index): A “preview” area where you select the changes you want to include in your next commit.
  3. Local Repository: The .git directory inside your project, where Git stores all the commits (snapshots) and other metadata.
  4. Remote Repository (Optional, but crucial for collaboration): A copy of the repository hosted on a server (e.g., GitHub, GitLab).

Typical Workflow:

  1. Make Changes: Modify files in your working directory.
  2. Stage Changes: Use git add to add specific files or changes to the staging area.
  3. Commit Changes: Use git commit to create a snapshot of the staged changes, along with a descriptive message. This saves the snapshot in your local repository.
  4. Push Changes (if collaborating): Use git push to upload your local commits to a remote repository.
  5. Pull Changes (if collaborating): Use git pull to download changes from the remote repository and merge them into your local branch.
  6. Create a Branch: Use git branch <branch_name> to create a new branch.
  7. Switch to a Branch: Use git checkout <branch_name> or git switch <branch_name> (a newer, more user-friendly command) to switch to a different branch.
  8. Merge a branch: Use git merge <branch_name> to merge changes from the specified branch into your current branch.

This workflow allows for organized, tracked, and collaborative development. The staging area provides a crucial step for carefully reviewing and selecting changes before committing them. Branching enables parallel development without interference, and remote repositories facilitate collaboration and backup.

You can look at this Git Merge Conflicts tutorial to see how to handle merge conflicts.