Comment by e3b0c

I learned that Git stores data as DAG at the very beginning when introduced to it. But I came to get clicked until I realized that it is not only a DAG but an immutable one. That is, existing nodes of the DAG are never changed once created. The only operation supported by the system is more or less: create. Also, using the plumbings to peek into the content of the objects and refs inside the .git helps a lot as well.