Git Basics

Table of Contents

1. Initialize a Git Repository #

$ git init

This will create .git directory to store all information for version control.

2. Checking out a Remote Repository #

$ git checkout https://github.com/username/abc.git
$ git checkout https://github.com/username/abc.git branch_name

The last .git can be omitted. This will copy files in the remote repository. You can directly checkout a branch by adding branch_name to the tail of the command.

To checkout a remote branch into the existing git local repository, use the following:

$ git fetch
$ git checkout branch_name

3. Commit / Push #

$ git commit -m "commit message"
$ git push origin branch_name  (e.g. git push origin master)

Unlike SVN, git has two steps to apply changes to a remote repository. First is commit, record a checkpoint in local repository, and the next is push, transfer it into remote repository.

origin in push command means the remote repository you checked out.

4. Git branch_name #

Branch is a beauty of git. You can work with coworkers without any interference with them.

Creating a branch
```
$ git branch branch_name
```
This will create a local branch with the name branch_name. Then you can switch your branch to this by git checkout branch_name.
Listing branches

You can see the list of branches by typing the following command.
```
$ git branch --list (-l)
```
Or, if you also want to see branches in a remote repository, type the following.
```
$ git branch --all (-a)
```
Merging branches

To merge two branches, first go to the branch that will be a base. In most case, it will be master branch. Then merge with the target branch.
```
$ git checkout master
$ git merge branch_name
```
Deleting a branch

After merging two branches, they still remain. If you complete your work in a branch, you can delete it by
```
$ git branch --delete branch_name
```
Or if you want to remove a branch in a remote repository, you can type
```
$ git branch --delete branch_name
$ git push origin :branch_name
```
colon (:) is the key. After deleting a local branch, push this change into the remote repository.