Workshop: Introduction to version control

Why use version control? The two advantages that version control provides:

You are able to travel back in time to any point in a project and utilize it from that moment; and
if you use a remote, collaboration is not only straightforward, it is encouraged.

This page's examples assume you are using git.

Required tools

A VCS - preferably git.
A web-based system to host your remotes. Bitbucket is recommended because it offers free private repos for small teams, but Github is the most widely used web-based repository.

Git is accessed through the command line interface (CLI) of your choice:

Windows: you can use Git Bash (which was installed when you installed git.)
Linux/OSX: terminal (which is installed with the operating system)

Setting up a repo

There are several ways to do this; the easiest way is to create a new repo on Bitbucket or Github, and then duplicate it on your local machine using a CLI of your choice:

Navigate to the place you'd like to save the repo folder: cd [path]
Locate and copy the url for the git remote; in bitbucket, this is in the top-right corner of the repo's main page.
Use the clone function of git to download a copy of the repo locally: git clone [the_link_you_copied_in_step_2.git]

You can now begin adding files in your repo!

Using a repo

Typical workflow

When working on a project locally, your workflow will typically consist of the following:

Modify files within the repository's folder (e.g. changing lines of code).
Stage those changes: git add [filename]
Commit those changes to the repository: git commit -m "[a message describing the changes]"

If you have a remote set up, then two steps bookend the workflow above:

Pull any changes from the remote repository to your local copy: git pull
Modify files within the repository's folder (e.g. changing lines of code).
Stage those changes: git add [filename]
Commit those changes to the repository: git commit -m "[a message describing the changes]"
Push the new commit to the remote repository: git push [remote name] [branch name]

Common git commands

Command	Syntax	Function	Example usage
status	`git status [options]`	checks the status of the repo; shows a visual distinguishing among files which have and haven't been included in the repo, files which have been modified and staged, et al.	`git status`
add	`git add [filename]`	stages files; these files are ready to be committed.	`git add README.md`
commit	`git commit -m "[commit message]"`	commits changes to the repo, or "taking a snapshot".	`git commit -m "changed header"`
log	`git log [options]`	shows a list of all the previous commits in the current branch.	`git log`
checkout	`git checkout [branch or snapshot name]`	rolls the repository over in time to a particular snapshot; typically snapshots are referenced by a hash	`git checkout a65f27`
pull	`git pull [options]`	checks the remote for any new commits not on your local timeline; if so, downloads them to your local repo, then fast-forwards your local repo to the current snapshot	`git pull`
push	`git push [remote name] [branch name]`	connects to the remote and copies any new snapshots on your system to it	`git push origin master`