Core Git Command Reference

Git Subcommand	Purpose
add	Stage file changes to the index for upcoming commits
bisect	Locate the commit that introduced a bug using binary search
branch	Manage repository branches (list, create, delete)
checkout	Switch between branches or restore working tree files; use -b to create and switch simultaneously
clone	Copy an existing remote repository into a new local directory
commit	Save staged index changes to the local repository with a descriptive message
diff	Compare changes between working tree, index, local commits, or remote branches
fetch	Download latest objects and references from a remote without merging
grep	Search repository content for a matching pattern
init	Initialize a new empty Git repository in the current directory
log	Display commit history; use reflog to track local HEAD movements
merge	Combine two or more separate development histories into one
mv	Rename or move tracked files, directories, or symlinks
pull	Fetch remote changes and merge them into the current local branch
push	Upload local commits and update references on a remote repository
rebase	Reapply local commits on top of an updated upstream branch
reset	Adjust the current HEAD and optionally working tree/index to a specified state; --hard discards all uncommitted and staged changes
rm	Remove files from tracking and/or working tree; --cached removes only from index, -f removes from both index and local filesystem
show	Display detailed information about Git objects (commits, tags, blobs, trees)
status	Show current working tree and index state (untracked, modified, staged files)
tag	Create, list, delete, or verify GPG-signed version tags

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Staging and Initial Commit Workflow

Start by initializing or navigating to a Git-enabled directory, then stage all modified/new files:

# Stage all files recursively
git add --all

# Verify staging status
git status

Output example after staging:

On branch main

No commits yet

Changes to be committed:
  (use "git rm --cached <file>..." to unstage)
        new file:   project-notes.md

Staged files are referenced in .git/index, with content stored as compressed objects in .git/objects/. To inspect the hidden .git directory structure:

cd /path/to/repo
tree -L 2 .git/

Commit staged changes to the local repository with a clear message:

git commit -m "Initialize repository with project documentation"

Successful commit output:

[main (root-commit) 7c2a9f1] Initialize repository with project documentation
 1 file changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 project-notes.md

Check status again to confirm a clean working tree:

git status

Output:

On branch main
nothing to commit, working tree clean

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File Management Operations

Removing Tracked Files

Remove only from the index (keep local file):

git rm --cached temporary-file.txt

Remove from both index and local filesystem:

git rm -f deprecated-script.sh

Renaming Tracked Files

For unstaged files, use standard Linux mv:

mv old-filename.txt new-filename.txt

For already staged files, use Git's native rename to preserve history:

git mv old-staged-name.md updated-staged-name.md

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Commmit History Exploration

Basic and advanced history queries:

# Show full commit history
git log

# Show last 3 commits
git log -3

# Show diff of the most recent commit
git log -p -1

# Show file change statistics for last 2 commits
git log --stat -2

# Show condensed one-line history
git log --pretty=oneline

# Show detailed history with author and committer info
git log --pretty=fuller -2

# Custom format output (short hash + author name + commit subject)
git log --pretty=format:"%h | %an | %s"

Custom Log Format Placeholders

Placeholder	Description
%s	Commit subject line
%cd	Commit date (uses local timezone)
%an	Author's full name
%cn	Committer's full name
%ce	Committer's email address
%H	Full 40-character SHA-1 commit hash
%h	Abbreviated 7-character SHA-1 commit hash
%T	Full SHA-1 tree hash
%t	Abbreviated SHA-1 tree hash
%P	Full SHA-1 parent commit hashes
%p	Abbreviated SHA-1 parent commit hashes
%ad	Author's revision date

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Version Rollback and Recovery

Rollback to Past Commits

Git uses a HEAD pointer to track the current branch tip. Rollback by resetting HEAD:

# First get target commit hash
git log --pretty=oneline

# Hard reset (discard all changes after target)
git reset --hard 7c2a9f1

# Soft reset (keep changes staged)
git reset --soft HEAD~2

# Mixed reset (keep changes unstaged; default behavior)
git reset --mixed HEAD^3

Restore "Lost" Future Commits

Use reflog to track local HEAD movements, even for discarded commits:

# View reflog entries
git reflog

# Restore to a specific reflog state
git reset --hard HEAD@{2}

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Git Tag Usage

Tags mark specific commits (e.g., releases). Create lightweight or annotated tags:

# Create lightweight tag (no metadata)
git tag v0.1.0

# Create annotated tag with message and optional GPG sign (-s)
git tag -a v0.2.0 -m "Beta release with UI improvements"

# List all tags
git tag

# Filter tags by pattern
git tag -l "v0.*"

# View tag details
git show v0.2.0

# Delete a local tag
git tag -d v0.1.0

Use tags for rollback directly:

git reset --hard v0.2.0

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Change Comparison Tools

Compare file content across differant Git states:

# Compare working tree to staged changes
git diff project-notes.md

# Compare staged changes to last commit
git diff --cached

# Compare two specific commits by hash
git diff 7c2a9f1 a3d4b7c

# List only changed files between two commits
git diff --name-only HEAD HEAD~