HEAD is a reference to master.
If any reference pointing to another reference, such type of reference is called symbolic
reference. Hence HEAD is symbolic reference.
Bydefault HEAD is always pointing to branch(master).
$ git log --oneline
49aa8d7 (HEAD -> master) both files added
HEAD is stored in root of .git directory but not in .git/refs directory.
$ cat HEAD
ref: refs/heads/master