What is HEAD in Git?

Question

You see the Git documentation saying things like

The branch must be fully merged in HEAD.

But what is Git HEAD exac

Answer 1

In addition to all definitions, the thing that stuck in my mind was, when you make a commit, GIT creates a commit object within the repository. Commit objects should have a parent ( or multiple parents if it is a merge commit). Now, how does git know the parent of the current commit? So HEAD is a pointer to the (reference of the) last commit which will become the parent of the current commit.