Version Control with Git: Git Cheatsheets for Quick Reference

Key Points

Automated Version Control

  • Version control is like an unlimited ‘undo’.

  • Version control also allows many people to work in parallel.
Setting Up Git

  • Use git config with the --global option to configure a user name, email address, editor, and other preferences once per machine.
Creating a Repository

  • git init initializes a repository.

  • Git stores all of its repository data in the .git directory.
Tracking Changes

  • git status shows the status of a repository.

  • Files can be stored in a project’s working directory (which users see), the staging area (where the next commit is being built up) and the local repository (where commits are permanently recorded).

  • git add puts files in the staging area.

  • git commit saves the staged content as a new commit in the local repository.

  • Write a commit message that accurately describes your changes.
Exploring History

  • git diff displays differences between commits.

  • git checkout recovers old versions of files.
Ignoring Things

  • The .gitignore file tells Git what files to ignore.
Remotes in GitHub

  • A local Git repository can be connected to one or more remote repositories.

  • Use the SSH protocol to connect to remote repositories.

  • git push copies changes from a local repository to a remote repository.

  • git pull copies changes from a remote repository to a local repository.
Collaborating

  • git clone copies a remote repository to create a local repository with a remote called origin automatically set up.
Conflicts

  • Conflicts occur when two or more people change the same lines of the same file.

  • The version control system does not allow people to overwrite each other’s changes blindly, but highlights conflicts so that they can be resolved.

Git Cheatsheets for Quick Reference

Glossary

add
To stage changes that you wish to commit. You can commit all the files that have been modified since your last commit, or just one. The git add command is used to stage changes you wish to commit. View documentation for git add command
branch
A branch in Git is a lightweight movable pointer to a commit. While working on a project, collaborators may make numerous branches to separate workflows such as feature development or bug fixes. The git branch command is used to create new branches. View documentation for git branch command
changeset
A group of changes to one or more files that are or will be added to a single commit in a version control repository.
checkout
To load the project state at a specific point in its history, such as a branch or commit. View documentation for git checkout command
commit
To record the current state of a set of files (a changeset) in a version control repository. As a noun, the result of committing, i.e. a recorded changeset in a repository. If a commit contains changes to multiple files, all of the changes are recorded together. The git commit command is used to create a commit. View documentation for git commit command
conflict
A change made by one user of a version control system that is incompatible with changes made by other users. Helping users resolve conflicts is one of version control’s major tasks.
HTTP
The Hypertext Transfer Protocol used for sharing web pages and other data on the World Wide Web.
merge
(a repository): To reconcile two sets of changes to a repository. The git merge command is used to merge the sets of changes. View documentation for git merge command
protocol
A set of rules that define how one computer communicates with another. Common protocols on the Internet include HTTP and SSH.
pull
To bring in updates from a remote repository repository to a local repository. The git pull command is used to pull changes from the associated remote branch to a branch in a local repository. View documentation for git pull command
push
To send updates from a local repository to a remote repository. The git push command is used to upload local repository content to a remote repository. View documentation for git push command
remote
(of a repository) A version control repository connected to another, in such way that both can be kept in sync exchanging commits.
repository
A storage area where a version control system stores the full history of commits of a project and information about who changed what, when.
resolve
To eliminate the conflicts between two or more incompatible changes to a file or set of files being managed by a version control system.
revision
A synonym for commit.
SHA-1
SHA-1 hashes is what Git uses to compute identifiers, including for commits. To compute these, Git uses not only the actual change of a commit, but also its metadata (such as date, author, message), including the identifiers of all commits of preceding changes. This makes Git commit IDs virtually unique. I.e., the likelihood that two commits made independently, even of the same change, receive the same ID is exceedingly small.
SSH
The Secure Shell protocol used for secure communication between computers.
timestamp
A record of when a particular event occurred.
version control
A tool for managing changes to a set of files. Each set of changes creates a new commit of the files; the version control system allows users to recover old commits reliably, and helps manage conflicting changes made by different users.