What is “Staging Area” or “Index” in GIT?

Question

Q:

What is “Staging Area” or “Index” in GIT?

Answer 1

Before finishing the submits, it can be organized and inspected in the middle of the road zone known as ‘Arranging Area’ or ‘Index’.

Answer 2

That before completing the commits, it can be formatted and reviewed in an intermediate area known as ‘Staging Area’ or ‘Index’. From the diagram it is evident that every change is first verified in the staging area I have termed it as “stage file” and then that change is committed to the repository.