Guide to Git™ — Common Git Terms

Last modified: November 13, 2024


Overview

Git™ is a version-control system that tracks and manages changes to files. Whenever content changes, Git records it and stores the content’s history. Because of Git’s complex functionality, it uses many terms that novice users may not immediately understand.

To learn about how these terms work in context, read our Common Git Commands documentation.

Common Git terms

Archive

Archives store the contents of the current working tree, but not the .git directory or uncommitted changes, in a .zip or .tar file. You may wish to create an archive to provide a source download file.

Branch

Each branch in a repository represents a separate line of development, and all branches retain their own project history, working directory, and staging area. Each repository can contain as many branches as you wish to create, but you can only work in one branch at any given time. Generally, branches diverge from the original line of development with the intent to merge the branch’s changes at a later time.

Check out

Git uses this term in two contexts:

  • Git uses git checkout to switch between multiple branches from the command line. When you check out a branch or commit via the git checkout command, Git points HEAD to the specified branch or commit.
  • When you check out files via the git checkout command, Git copies the version of that file from the specified commit or from the index. This allows you to revert committed or uncommitted changes. For example, if you wanted to delete your local changes to example.js in your test branch, you would run the following commands:
    1. git checkout test — This use of git checkout switches you from your current Git branch to the test branch, where you will copy the example.js file.
    2. git checkout -- example.js — This use of git checkout switches you from your local test branch’s version of example.js to the remote test branch’s version of example.js. This deletes your local changes.

Cherry-pick

When you cherry-pick changes via the git cherry-pick command, Git applies the specified changes from a commit and branch to a different branch’s HEAD.

Clone

When you clone a public repository via the git clone command, Git performs the following actions:

  1. Git creates a new local repository in the directory in which you ran the command.
    Note:

    When you clone a repository in cPanel’s Git Version Control interface (cPanel » Home » Files » Git Version Control), the system creates the repository in the Repository Path directory that you specify.

  2. Git sets the remote repository that you wish to clone as the origin remote repository.
  3. Git fetches all of the commits and branches from the remote repository.
  4. Git checks out the default branch. Generally, this branch is named master or main.

You can then make changes to the local repository and push them to the remote repository, as well as pull changes.

To clone private repositories, you must perform additional steps. For more information, read our Set Up Access to Private Repositories documentation.

Commit

Commits represent a point in Git’s history. Git’s entire history for a repository exists as a timeline of individual commits. When you commit changes, you create a new point in the history that represents the current state of the index. HEAD then points to the new commit.

Commit Object

Commit objects represent your committed revisions to a branch. Each commit object contains the commit’s files (the tree object), parent commits, commit metadata (for example, the author and date), and a SHA-1 value that identifies the object.

Deployment

Deployment sends finished code into production. You can use different configurations to automatically or manually deploy changes.

For example, you can configure cPanel’s Git Version Control interface (cPanel » Home » Files » Git Version Control) to automatically deploy changes that a cPanel-managed repository receives.

For more information, read our Set Up Deployment documentation.

Fetch

When you fetch changes via the git fetch command, Git automatically downloads new changes from the remote repository. However, it does not merge these changes into the working tree for any local branch.

Fork

When you fork a repository, you create a new server-side copy of that repository. You can then experiment with changes to that repository without any impact on the original repository.

The HEAD value represents the SHA-1 identifier for the most-recent commit or active branch. Whenever you commit changes to the active branch, Git automatically updates HEAD to that commit’s SHA-1 identifier. If you use the git checkout command to check out a specific commit instead of a branch, Git enters the detached HEAD state.

Head

Heads are the SHA-1 identifiers for the most-recent commits to each branch. While only one HEAD commit exists, a repository generally contains many heads for each branch.

Hook

Hooks are scripts or other code that you can configure to trigger before or after specific Git actions. You can store these hooks in the /hooks directory within the repository directory.

Note:

cPanel’s Git Version Control interface (cPanel » Home » Files » Git Version Control) automatically adds a post-receive hook to cPanel-managed repositories.

Index (Staging Area, Cache)

Indexes contain the files from your working tree that you add to a commit to the Git repository. Git also uses the index to store data during failed merges.

Log

The log contains the commit hash and metadata, such as the commit message, for every commit on the current branch. You can access this data via the git log command on the command line or via Gitweb in cPanel’s Git Version Control interface (cPanel » Home » Files » Git Version Control).

Master or main

Generally, the default branch for a repository is the master or main branch. When you commit changes to it, Git moves the default branch’s HEAD to the most recent commit’s SHA-1 identifier.

Merge

When you merge one or more commits, Git adds changes to the current branch. To perform a merge of this type, run the git push command.

You may also need to manually merge specific revisions if they conflict with changes that have already merged into the repository.

  • This type of merge uses the git merge command.
  • The term “merge” may also refer to the commit that this type of merge creates.

Origin

Origin is Git’s default name for the remote repository from which you cloned a local repository. Most repositories include at least one origin repository. Software development often refers to origin as “upstream”.

Pull

When you pull changes from the remote repository via the git pull command, Git fetches remote changes and then merges them into the current branch.

Note:

You can use the Pull from Remote feature in cPanel’s Git Version Control interface (cPanel » Home » Files » Git Version Control) to automatically pull changes for a repository’s active branch.

Push

When you push changes via the git push command, Git sends commits from your local branch to the remote repository.

Rebase

Rebases reapply changes to the history of the active branch via the git rebase command. To do this, rebases eliminate merge commits and create a new commit for each commit in the original branch.

Remote (Remote Repository)

The remote repository exists on a remote filesystem. When you fetch, pull, or push code, Git sends changes to or receives changes from the remote repository.

Repository

Repositories store all of the data that Git manages for a specific project. It contains commit objects and heads as well as the working tree.

SHA-1 (SHA-1 sum, Hash)

The algorithm that generates the names for all Git objects, from commit objects to stash objects. In Git’s vernacular, this term also refers to the 40-character hexidecimal string that the algorithm generates.

Stash

An object that stores changes to the working tree and index for future reuse. The stash allows you to set aside changes to a branch and return to the HEAD state. You can then reapply the stashed changes or apply them to a different branch.

Version Control

Version control systems track changes in files and allow multiple users to coordinate those changes and view and manipulate the project’s history. Git is a version control system.

Working Tree

The working tree contains the checked-out file system for a repository. The working tree includes the files for the HEAD commit and any local changes to those files.