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So now that we know that Git is a version control system, a popular one at that, let's talk more about

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the specific features.

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What does it do for us?

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So in this slide we can see some of the main things get helps us with it helps track changes across

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files, compare versions of a project, time travel back to old versions.

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Take a peek at what something looks like a year ago.

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Take a look at Facebook's code base today compared to two days ago.

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Go back to a previous version if we messed something up, combine different changes between versions,

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between different files, between different collaborators.

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And that's probably the most important part.

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Collaborate and share changes get facilitates collaboration between a team of users.

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If developers of writers, whatever people are doing with Git Get facilitates collaboration and sharing

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those changes between individual people.

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So here's a very, very simple explanation.

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If you've ever played video games like I have, there are some games that allow you to make save points

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that will check points you can come back to.

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And I guess this is supposed to be me.

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I was always very, very nervous as a game player.

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Some of the games I played as a kid where if you died, you would go all the way back to wherever your

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last save was.

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So I would always try and save before well, pretty much before anything.

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So I would save and then get to some horrible boss battle.

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I suck at video games even though I like them.

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I die.

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But that's okay.

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I don't get angry because I saved my game.

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I can just go back to that save point.

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That is the simplest, simplest explanation of JIT and what it allows us to do.

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Set up these checkpoints.

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You can screw things up entirely, make a huge mess of a code base or of a project, empty all the files

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out, delete the files.

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But if you're using Git and you made these checkpoints, you can just go back.

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So here's another explanation that I've used in high school.

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In college I had to write a lot of essays.

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I did not know Git really at the time.

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So I did this.

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I would start writing an essay and then I wanted to try something new so I'd save as I'd make a new

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version that was V one or V two or even more variations v two with a new intro or a new conclusion or

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reorder all sorts of different strategies.

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And I would save all of them because I wanted to be able to compare.

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I didn't want to just have one essay that I had to work in.

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I want to be able to track versions and compare, and it's just part of the process.

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And then I would end up with some final, but then inevitably actually final, final for real.

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This is the one print, this one.

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This was honestly what I did in high school and college all the time.

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So get helps with this sort of issue.

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Now this is a very trivial situation, but imagine thousands of developers collaborating on a project

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where they're working on millions of lines of code all at the same time, and having these different

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versions and sharing and combining them.

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So here's a somewhat more realistic example.

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I'm working on some project, a website.

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This is the progress of the website up top.

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So right now it's empty.

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With Git, I create checkpoints, so checkpoints are like save files I can go back to.

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So I have my first checkpoint initialize project.

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There's nothing up there.

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But then I do some work.

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I add this nav bar up top, so I make a new checkpoint, add top nav bar.

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Now I have two checkpoints and then I do more work, write some content.

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So I add a new checkpoint.

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We'll say Add first row, whatever this is.

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Maybe I'm making YouTube or something, so I add some content and then I do more work, I add more content,

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I add a new checkpoint.

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This workflow is very, very common.

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You do something in a project.

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If you're using Git, you make one of these so called checkpoints.

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We'll learn what they are and how you do it, of course, and then you keep working.

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So here I changed the theme entirely.

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A dark theme, new fonts, new colors, new everything.

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I add a checkpoint.

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So I forgot to mention I work not alone on this.

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I'm working at a company.

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I have a boss.

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I'm not the one making these decisions.

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Right?

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What stays if we want this theme or not, or if we want this earlier theme here.

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But anyway, I do some more work.

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I alter the naff bar color, I make it yellow, I add a checkpoint, update nav bar, and then I show

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it to my boss.

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Realistically, you don't just show code to your boss, but there's a process for approving or rejecting

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changes.

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But anyway, in this simplistic world, my boss gets angry, or maybe not even angry.

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She just says, You know what?

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These colors suck.

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We can't move forward with that.

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But that's okay.

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I use Git.

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I have this series of checkpoints.

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I can go back in time to earlier checkpoints.

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So this is what it looked like at this checkpoint.

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But I can go backwards too.

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So from before the time I added the dark theme.

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Now we're back to this light theme, and then I could even branch off.

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I could start working from this point and create a new sort of fork where I can have an alternate timeline.

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So this works.

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Not lost.

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I'm just not doing it right now.

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I'm.

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Working on a new version.

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So I added more content if you can see that there.

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So I had two rows of content.

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I add more content.

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Now I've picked up development at this point in time.

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So I add a third row, maybe I add a new footer down there.

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So we get a new check point.

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If I want to add a check point then and then I could switch back to what I had earlier.

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At this point, I can toggle between them.

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I can use Git to say go all the way back to when I first added the nap bar or go all the way up to when

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I updated the nap bar.

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I made it yellow or go to add footer.

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I can hop around and compare and I could present both to my boss.

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They both can exist, which is the crazy part.

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It helps us manage all of these different versions so I can switch back to this dark mode checkpoint.

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But what's even crazier?

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I can even combine these checkpoints, the work, the changes between the two.

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So this dark mode had the dark colors and add footer, had all this extra content with a footer and

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a third row.

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So I combined them to end up with a footer and a third row of content and the dark mode colors.

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So I now have a hybrid and that's exactly the sort of thing that it helps us with.

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Now this is a simplified example, but imagine now I'm working on a project.

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It's not just me.

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There's ten people or 100 developers, lots of files, lots of versions.

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How do we coordinate all those changes between all of us and combine them?

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Right?

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We don't all just work in silos on our own.

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We need to combine that work back into some code base at some points or whatever we're working on.

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We share those changes.

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So it's this times hundreds and hundreds, often at a large company.

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Okay, so that's the basic idea of Git and what it can help us with, just trying to visualize it for

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you.

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Next up, I guess totally optional.

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I'm going to talk about the history of Git.