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In this video, you’ll get an overview of
Git and GitHub, which are popular environments

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among developers and data scientists for performing version control of source code files and projects

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and collaborating with others.

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You can’t talk about Git and GitHub without a basic understanding of what version control is.

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A version control system allows you to keep track of changes to your documents.

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This makes it easy for you to recover older versions of your document if you make a mistake,

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and it makes collaboration with others much easier.

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Here is an example to illustrate how version control works.

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Let’s say you’ve got a shopping list and
you want your roommates to confirm the things

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you need and add additional items.

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Without version control, you’ve got a big
mess to clean up before you can go shopping.

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With version control, you know EXACTLY what you need after everyone has contributed their ideas.

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Git is free and open source software distributed under the GNU General Public License.

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Git is a distributed version control system,
which means that users anywhere in the world

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can have a copy of your project on their own computer; when they’ve made changes, they

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can sync their version to a remote server
to share it with you.

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Git isn’t the only version control system
out there, but the distributed aspect is one

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of the main reasons it’s become one of the most common version control systems available.

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Version control systems are widely used for things involving code, but you can also version

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control images, documents, and any number of file types.

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You can use Git without a web interface by using your command line interface, but

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GitHub is one of the most popular web-hosted services for Git repositories.

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Others include GitLab, BitBucket, and Beanstalk.

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There are a few basic terms that you will
need to know before you can get started.

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The SSH protocol is a method for secure remote login from one computer to another.

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A repository contains your project folders
that are set up for version control.

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A fork is a copy of a repository.

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A pull request is the way you request that
someone reviews and approves your changes

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before they become final.

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A working directory contains the files and
subdirectories on your computer that are associated

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with a Git repository.

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There are a few basic Git commands that you will always use.

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When starting out with a new repository, you only need create it once: either locally,

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and then push to GitHub, or by cloning an
existing repository by using the command "git init".

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"git add" moves changes from the working directory to the staging area.

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"git status" allows you to see the state of
your working directory and the staged snapshot

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of your changes.

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"git commit" takes your staged snapshot of changes and commits them to the project.

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"git reset" undoes changes that you’ve made to the files in your working directory.

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"git log" enables you to browse previous changes to a project.

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"git branch" lets you create an isolated environment within your repository to make changes.

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"git checkout" lets you see and change existing branches.

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"git merge" lets you put everything back together again.

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To learn how to use Git effectively and begin collaborating with data scientists around

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the world, you will need to learn the essential commands.

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Luckily for us, GitHub has amazing resources available to help you get started.

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Go to try.github.io to download the cheat
sheets and run through the tutorials.

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In the following modules, we'll give you a
crash course on setting up your local environment

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and getting started on a project.