Git branches and HEAD
Most common operation
- We have three git areas i.e., Working directory, Staging area and Git repository.
- To move our files from working directory to staging area (index) we use
git addcommand. - To move our files from staging area (index) to Git repository we use
git commitcommand.
A commit consist multiple information such as - Author Name, Date, Message
- To move between/certain "version" in our git repository we use
git checkoutcommand
File States in Git areas
- When we add new file to working directory it becomes
untracked(only exist in working directory area). - Once the file added in staging area it becomes
staged - Once we make commit to that file it get into Git Repository.
- Once we make new changes after commit the state turn into
modifiedin all the three areas.
Branch
- A branch is essentially a pointer to a specific commit in your project's history.
- It's like creating a parallel timeline where you can make changes independently without affecting the main project.
- Default branch is master
- Multiple branches can exist in the same repository
- Pointers for all branches are located in
.git/refs/headfolder - Current branch tracks new commits
- Branch pointer moves automatically after every new commit
- Change branch
git checkout <branch_name> - Each branch has it's own isolated commit history
Git Branch
ubuntu $ git branch
* master
ubuntu $ ls -l .git/refs/head
total 4
-rw-r--r-- 1 root root 41 Nov 3 16:44 master
ubuntu $ cat master
beeaef1a2978c59e530723f7466da668f10243bd
ubuntu $ git log
commit beeaef1a2978c59e530723f7466da668f10243bd (HEAD -> master)
Author: Xander <xanderbilla@gmail.com>
Date: Sun Nov 3 16:44:14 2024 +0000
First commitHEAD
- HEAD is used by branch to point the checkout commit or a branch
- There will be only one HEAD
- HEAD is locally significant
- Pointer is located in the
.git/HEADfile. - Default pointer is
ref: refs/heads/master - Change reference to specific branch
git checkout <branch> - Change reference to specific commit
git checkout <sha1>