• Each object has a type, a size and a content


• Each object is identified by a 40-digit SHA1 hash of attributes
  • 6ff87c4664981e4397625791c8ea3bbb5f2279a3


• Each SHA1 can be shortened to the first digits
  • 6ff87c4664981e4397625
  • 6ff87c4


• Object type can be blob, tree, commit or tag

• Used to store file data


• Same content = same SHA1 = same blob


• See it as a file

• Associate names to blobs and other trees


• See it as a directory

• Used to snapshot a tree state


• Has tree, parent(s), author, commiter and comment attributes


• Not the same as SVN ones:
  • SVN store diffs
  • GIT store full state

• Reference an object


• Has object, type, tagger and comment attributes.


• Not used for lightweight tags
  • Simple pointer on a commit (like branches)

• A branch is simply a pointer to a certain commit.


• A branch is not aa GIT object (no SHA1)

Set your name and email:

$ git config --global core.name "Me"
$ git config --global core.email "me@company.com">

Display your config

$ git config --global
$ git config --local  # in a repository

Stage your changes:

# Add to index / stage
$ git add file.txt
# Add all modified and new files (tracked or not) to index
$ git add -A
# Partial staging
$ git add -p file.txt

Create a commit into the current branch:

# Commit from index
$ git commit 
# Commit from tracked file list 
$ git commit file1.txt file2.txt 
# All modified tracked files 
$ git commit -a 
# Commit from pattern 
$ git commit **/*.py

See the current status:

$ git status

# Log integral 
$ git log 
# 5 dernier commits 
$ git log -5 
# Diff between two branches
$ git log origin/master..master

$ git branch feature     # Create the branch
$ git checkout feature   # Switch to the new branch 
# or in a single command 
$ git checkout -b feature

Branches diverge when they have different commits

Create a merge commit and keep your branch history:

$ git merge feature

Re-apply your commits and keeps your history linear:

$ git rebase master 
# or interactive version
$ git rebase -i master

$git remote add origin git://somewhere.git 
$git fetch

It’s just more branches !