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We've told you that Git can
keep you from losing work and

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that it can help teams
work together on projects.

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But how exactly does it do that?

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Git is a version control system.

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It helps you control the different
versions of the files in your project.

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It keeps track of all the changes
to your files over time.

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If you ask it to, it can reset any files
contents to match a previous version.

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Or, more commonly,

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you can reset the version of all
the project files at the same time.

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The collection of all the old
versions of your projects files

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is known as a Git repository.

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It's basically a folder in
which you can edit your files

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then run Git commands
to store your changes.

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You can have multiple Git repositories
on your computer, one for

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each project you're working on.

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So at this point you may be
thinking Git is just like

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network backup software like Dropbox or
Google Drive, right?

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After all,

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those programs store a new version of
a file every time you save it too.

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But Git is way more powerful
than just making backups.

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For one thing, it's intended to help
developers work together on a project.

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With just a couple commands, you can clone
an entire repository to another computer.

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This clone will include the full
version history of all the files.

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Once they have the files
on their own machine,

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other people can make their own changes.

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And Git includes commands that
let you easily bring changes from

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other people's repositories
back into your repository.

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Each time you complete a change to some or
all of your project's files,

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you can take a snapshot of
their current contents.

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This snapshot represents a point in your
project's history that you might want to

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travel back to some time in the future.

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These snapshots are known as commits.

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Just as you might take a phone number and
commit it to memory so

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you can remember it later, you can commit
a version of your projects files to

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your Git repository, so
you can get that version back later.

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But most version control
programs have features like this.

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Why is Git in particular so popular?

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There is a variety of reasons for
this, but here's an important one.

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Git is a distributed version control
system as opposed to a centralized system.

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In a centralized system, the repository
with all the old versions of files lives

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in only one place, a central server.

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If anything happens to
that central repo and

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you don't have current backups,
all the old versions will be lost.

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In a distributed system,
you can copy a complete repository

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with the full project history
to every developer's machine.

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Commands are available to synchronize
repos with each other as new

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changes are made.

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If anything happens to one of those repos,

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the data in any other repo
can be used to restore it.

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Let’s open up a workspace and
try our first Git command.

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It’s not going to look like much, but

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Git’s plain looking command line
interface hides some major power.

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You’ll see what we mean over
the rest of the course.

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If you’re watching this
video on the Treehouse site,

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there should be a Launch Workspace
button on the page, so click that.

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You'll see a dialog where you can
rename your workspace if you want.

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Click the Launch it
button when you're ready.

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A new window will open with
a Treehouse workspace.

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Give it a minute to load.

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You'll see the sidebar with the list
of files in this workspace, and

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a text editor, but we're not going
to use those much in this course.

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What we want is the console
panel down here at the bottom.

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Let's resize that so we have more room.

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Next, we need to activate the console.

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Click anywhere within the console panel.

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You'll know it's been activated if
a blinking cursor appears down there.

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This is a prompt for Bash,
a command shell that runs on many Mac,

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Linux, and even some Windows computers
when you open their terminals.

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This particular prompt shows
the current username and

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then the name of the directory or
folder that we're currently in.

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It's a directory named workspace,
in this case.

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Bash prompts usually end in a dollar sign.

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When you read Git tutorials out on
the web, you may see a dollar sign.

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That usually indicates that the text
following it should be typed at

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a shell prompt.

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Note that when following along with
a tutorial, you should not actually type

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the dollar sign unless it appears
somewhere in the middle of the command.

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Now we need to run Git.

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Git is installed on a system,
like it is here in this workspcae.

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It places an executable named git where
it should be run from any shell prompt.

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This is the git command.

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All the commands we're going to show
you during this course will use this

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executable.

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So they're all going to start
with git followed by a space.

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Then we need to specify the sub-command or
options we want.

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For this first command,
we're not going to run any sub-commands.

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We're just going to git help
on the git command itself.

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We do this with a command line option.

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Git options consist of either a single
dash followed by a single letter, or

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a double dash followed by a word.

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In this case, we want the help option.

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Once you've typed all that, your
command is complete, so press Enter or

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Return to run it.

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git --help will print out some
help on using the git program.

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By the way,

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it's okay if the output you see doesn't
exactly match what's shown here.

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It just means you're running
a different version of Git than I am.

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All the commands we show in this
course will work the same way

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no matter what version of Git you have.

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The only part of this output that's
really useful to us right now

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is this list of subcommands.

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These are used to invoke most
of Git's basic functionality.

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And we'll be trying out many
of them during this course.

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The git clone and git init commands
are used to set up new repositories.

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The git add, git status, and

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git commit commands are the most
frequently used subcommands in all of Git.

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They're used when committing
new versions of files.

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The git log command is also important.

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It lets you view a list
of your old commands.

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The git move and
git remove commands move and

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remove files that
are being tracked by Git.

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We'll learn about those in
stage two of this course.

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And the git push and git pull commands
are used to synchronize commits with Git

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repositories on other computers.

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We'll learn about those in stage three.

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That's an overview of
the most basic Git commands.

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Up next, we 'll show you how
to create a Git repository.