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Instructor: Hey, you're still sticking around.

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That's good, I didn't bore you

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with all my talking, but yes, in this video

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finally we're going to write some Python code.

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Holy moly.

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Thank God I thought that was gonna last forever.

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All right, so what is our first program going to do?

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Well, let's create a very, very simple function.

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And probably the first thing

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any programmer learns to do, to print our own name.

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So in here, once you have your repl.it set up

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or remember you can also use glot.io.

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We're simply going to write print.

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And then you see over here

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that it gives us some information,

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but all we wanna do is write brackets, a quote.

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So you can do double quotes here

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or a single quote and just type your name.

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And if we click run on the right side,

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we've just ran our very first Python program.

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Very exciting.

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But what's happening here?

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Well, let's look at everything.

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First of all, if you're confused why my thing is darkened,

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yours might be light.

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It's because if I go to settings,

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I've set my theme to light or to dark.

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I prefer the dark version.

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But you can change some of your settings.

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You can change the font size if you want,

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based on when you watch the video.

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This website, the look might be different

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but most of the settings should be the same.

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We see that we have a main.py,

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which is the Python extension.

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Any file that has a .py or py is a Python file.

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So what we've just written here

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on line one is a program that prints

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in this case Andrei Neagoie or in your case, your own name.

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And we've written it to this file.

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Now, repl.it takes this file

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already has this interpreter for us.

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It runs this piece of code, gives this source code

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of main.py to the interpreter and runs it right here

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on our right side.

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If you look over here, we're using Python version 3.6 0.1

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and down below we see that,

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Oh, we have Andrei Neagoie print it.

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That's awesome.

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So this is our code running.

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Remember this diagram?

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All we've done is we have our main.py

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where we wrote print Andrei Neagoie.

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We gave it to the interpreter that the repl

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already provides for us.

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That interpreter takes our code, converts it

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into bite code, and here it'll say Andrei Neagoie.

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And then it runs it in the CPython VM,

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which was on the right side that we saw.

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And it finally prints our name

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because it tells the machine,

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"hey we want that text printed".

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So that's what we're seeing here.

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This is the CPython virtual machine essentially

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running this code and telling this machine,

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"hey I want you to print this".

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All right, but this isn't very exciting.

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I mean, let's make this program a little bit more dynamic.

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For our first program,

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we wanna do something more impressive than just print name.

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So I'm going to teach you another thing we can do in Python

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and it's called input.

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Now, in here I can say input.

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And you see that repl actually gives me

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some information saying that, "Oh, I have this".

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You can just click here, and this input over here.

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Well, what can we do?

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This input is going to prompt a user.

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And if I hover over it, you can see how it's giving me

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some information.

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But input simply gives us a way to capture information.

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So let's say, what is your name?

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And if I run this code,

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we see that we have our Python code running,

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and it's asking me what is my name

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with this cursor here.

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So I can actually type something here.

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I can say Andrei, and if I hit enter, well, there you go.

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I've just typed in my own name.

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Nothing that exciting, right?

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But this is where code becomes interesting

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because we can store this information on our computer.

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So again, these are things that we're gonna go over

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in detail in our basics Python section,

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but just to write our first code.

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Let's assign this to memory.

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That is, let's say that name equals whatever is the input

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of what is your name.

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And then finally, we can just print the name.

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So remember the interpreter

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is going to take this first line.

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It's going to ask, What is your name?

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I'm going to type something, that typed information

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is going to get assigned to name.

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And then finally, we print name.

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Remember, an interpreter takes line by line,

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converts code to bite code, and then finally runs it.

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So let's give this a try.

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I'm going to click run.

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All right, what's your name?

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My name is Andrei.

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Did you see that?

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I typed in my name hit enter,

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and then it printed out Andrei.

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So for the final feed, let's greet.

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So we're going to say print hello, and then plus name.

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Now, don't worry about this syntax, we're gonna go over it,

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but all we're doing is saying hello

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and then adding our name to the end of this.

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So let's see what happens

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if I run this and say, What is your name?

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My name is Andrei and I hit enter.

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I get, "hello Andrei", but no spaces.

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So let's add a little space.

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Hit run again for the fourth time.

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My name's Andrei and it says, "hello, Andrei".

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There it is.

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Our first Python program.

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Now, it's not very exciting because it is our first program.

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We're just learning the steps here.

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But I hope because we've covered some of these topics

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ahead of time,

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that this isn't just pure magic, right?

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You understand that this is source code.

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This is main.py that we give

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to an interpreter that runs our code line by line

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and then executes our program.

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In this case, our what is your name program?

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How cool is that?

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This is just the beginning.

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We're gonna get more and more advanced here.

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See if you can play around with this.

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We don't know that much about Python yet

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but I hope this gets you excited because well,

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there's a lot more coding coming along.

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I'll see you in the next one.

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Bye-bye.