3c Resolving Merge Conflicts A merge conflict happens when Git can’t automatically combine changes from two branches. The same lines were touched in both, and Git refuses to guess which version should win. It stops the merge, marks the conflict in the affected files, and waits for you to decide. Key point: A conflict isn’t…
GitHub disabled password authentication for Git operations over HTTPS in August 2021. Passwords are reused, phished, and leaked in bulk; the replacements—SSH keys and personal access tokens—are revocable, scoped, and often time-limited . The choice between them is not about which is “better.” It is about which one matches the workflow: SSH keys for your…
Rebasing rewrites commit history by replaying your branch’s commits on top of another branch. Where merge creates a merge commit and preserves both branches, rebase produces a linear history — as if you’d always been working from the latest main. Key point: Rebase rewrites history. That’s its power and its danger. It gives you a…
git stash temporarily saves your uncommitted changes and reverts your working directory to the last commit. It’s the escape hatch for the moment you need to switch tasks but aren’t ready to commit — a half-finished feature, a file you forgot to add, a quick bug that needs attention. Key point: A stash is a…
Cherry-picking applies a specific commit from one branch onto another. Where merge brings an entire branch and rebase replays a range of commits, cherry-pick takes one commit at a time and copies its changes to wherever you are. Key point: Cherry-pick creates a new commit with a new hash. The original stays untouched. This makes…
A tag is a permanent label on a specific commit. Unlike branches, tags don’t move — once placed, they stay on that commit forever. That makes them perfect for marking releases: v1.0, v2.3.1, v1.0.0-rc.2. When someone asks “what code was in version 1.0?”, the tag answers immediately. Key point: A tag is a named pointer…
Every repository generates files that should never be committed — build artifacts, dependency folders, editor settings, secrets. .gitignore is how Git is told to look the other way. It’s the file that keeps a repository clean, focused, and safe. Key point: .gitignore only affects untracked files. If a file is already committed, adding it to…
On a shared repository, contributors who have write access can push branches directly. But on most open-source projects, contributors don’t have that access. Forking solves this — you make your own copy of the repository, push changes there, and then ask the original project to pull them in via a pull request. Key point: A…
A repository is the container that holds a project’s files and their complete revision history. Creating one on GitHub is a four-step form: name it, choose who can see it, optionally seed it with starter files, and click create. The visibility choice—public or private—is the only decision that cannot be changed without consequences, and the…
Good Git habits aren’t about following rules for their own sake — they’re about making history readable, reviewable, and reversible. A clean commit log tells a story. A messy one forces everyone to read diffs. This chapter covers the habits that separate a Git user from a Git practitioner. Key point: The goal of good…