Git: Tree-ish

Tree-ish is a way to refer to particular commits in Git using either full or partial hash of the commits, refs, branch, remotes, or a combination of these with those ^, ~, @ characters. I am still new to these, so appreciate any additions and corrections.

Reference: http://git-scm.com/book/en/Git-Tools-Revision-Selection

• Full hash:

  git show a5bec062afe1348b8317651c93cf5049e6b4e55e

• Partial hash:

  git show a5bec

• Some example of using refs (it's really anything you can find in .git/refs):

  git show HEAD
  git show FETCH_HEAD
  git show ORIG_HEAD
  git show MERGE_HEAD 

• Caret (^) - number of ancestors before a given commit:

  git show HEAD^   # direct parent of HEAD
  git show a5bec^^ # two commits before 

• Tildes (~) - number of commit to go back:

  git show HEAD~6  # 6 commits before HEAD

• Ordinal (@{n}):

  git reflog {ref} # shows a log of where your ref has been
  git show HEAD@{0}   # current HEAD
  git show HEAD@{2}   # second prior value of HEAD
  git show master@{0}  # current master
  git show master@{yesterday}  # where master was yesterday
  git show master@{1.week.ago} # where master was a week ago