# Using git version control

## Using git

如果你不太習慣從terminal (Mac)或cmd (Win)等command line來下指令，你可以[安裝github desktop](https://desktop.github.com/)來下載或管理自己的repository，視窗化的工具有助於你初步了解git這種版本控制工具要如何用。

> 我們將Terminal(Mac)或cmd(Win)這種工具稱為命令列工具（Command line）。

Command line要如何下可參考[joshnh](https://github.com/joshnh)/[Git-Command](https://github.com/joshnh/Git-Commands)的說明。初始化一個repository有兩種時機，一種是你要把電腦裡的一個資料夾放到github上，另一種是，你要把網路上的一個github repo clone到你的電腦裡，分別是以下兩個指令。

### Getting & Creating Projects

| Command                                                           | Description                                |
| ----------------------------------------------------------------- | ------------------------------------------ |
| `git init`                                                        | Initialize a local Git repository          |
| `git clone ssh://git@github.com/[username]/[repository-name].git` | Create a local copy of a remote repository |

除了初始化外，git有三個主要的動作

1. **commit**：提交任何變更，commit後不會寫到github，而且可以退回。
2. **push**：在提交變更後，把這些變更版本覆蓋到github上。
3. **pull**：把github上別人改過的版本拉下來，覆蓋掉自己電腦上的版本。

### Basic Snapshotting

| Command                            | Description                                       |
| ---------------------------------- | ------------------------------------------------- |
| `git status`                       | Check status                                      |
| `git add [file-name.txt]`          | Add a file to the staging area                    |
| `git add -A`                       | Add all new and changed files to the staging area |
| `git commit -m "[commit message]"` | Commit changes                                    |
| `git rm -r [file-name.txt]`        | Remove a file (or folder)                         |

### Sharing & Updating Projects

| Command                                                                           | Description                                                 |
| --------------------------------------------------------------------------------- | ----------------------------------------------------------- |
| `git push origin [branch name]`                                                   | Push a branch to your remote repository                     |
| `git push -u origin [branch name]`                                                | Push changes to remote repository (and remember the branch) |
| `git push`                                                                        | Push changes to remote repository (remembered branch)       |
| `git push origin --delete [branch name]`                                          | Delete a remote branch                                      |
| `git pull`                                                                        | Update local repository to the newest commit                |
| `git pull origin [branch name]`                                                   | Pull changes from remote repository                         |
| `git remote add origin ssh://git@github.com/[username]/[repository-name].git`     | Add a remote repository                                     |
| `git remote set-url origin ssh://git@github.com/[username]/[repository-name].git` | Set a repository's origin branch to SSH                     |