Git

## Git Blobs and trees

  ### Asking Git for the SHA1
    > echo 'Hello, World!' | git hash-object --stdin
    8ab686eafeb1f44702738c8b0f24f2567c36da6d

  ## Git Commits
  commit are stored in .git/objects

      tree .git/objects
  
  ### Print out the type of the commit
    git cat-file -f 980a0
    blob
    
  ### Print out the contents of the commit
    git cat-file -p 980a0
    Hello World!
    
  ## Git Staging
    git ls-files -s
    git add -P
  
  ## Git Stash
  #### Stach changes
    git statsh
  #### list changes
    git stash
  #### show the contents
  git statsh show stash@{0}
  ####apply the last stash
  git statsh apply
  #### apply a specific stash
  git stash apply stash@{0}
  #### remove a stash
  git stash drop stash@{0}
  ### remove all
  git stash clear
  
  Stash are visible from all branches !
  ## Tags
  
  tag is a pointer to a commit
  
      git tag "initial-commit" 
      
  list all tags in a repo
  
      git tag

list all tags, and what commit they're pointing to
  
      git show-ref --tags
List all the tags pointing at a commit
  
      git tag --points-at < commit >
Looking at the tag, or tagged contents:
    
    git show < tag-name >

list heads

    git show-ref --heads