Engineering Craft › Version Control (Git)

HEAD

Git's pointer to the commit you currently have checked out.

Also known as: Git HEAD, HEAD~1, HEAD pointer

HEAD is Git’s pointer to the commit you currently have checked out, usually through the branch you’re on. It answers “where am I now?”, and it’s the parent of the next commit you make.

main ─► C ─► B ─► A        HEAD ─► main      (HEAD points at the branch, which points at C)

When you commit, the branch moves forward, and HEAD follows it, because it points at the branch.

git log HEAD          # history from here
git diff HEAD         # changes since the last commit
git show HEAD         # the current commit
git reset --hard HEAD # throw away uncommitted changes

Relative references

You can name commits relative to HEAD:

git diff HEAD~1 HEAD           # what the last commit changed
git rebase -i HEAD~4           # edit the last four commits
git reset --soft HEAD~1        # undo the last commit, keep the changes

When HEAD doesn’t point at a branch

In a detached HEAD state, HEAD points straight at a commit, so new commits belong to no branch.

Where it lives

In the file .git/HEAD, typically containing ref: refs/heads/main. Its history of movements is recorded in the reflog, which is the safety net when you move it by mistake.

Don’t confuse HEAD with main or origin/main: those are other pointers.