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what's going on guys? This is bucky and this is the second c plus plus tutorial
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and in this tutorial what I am going to be doing is breaking apart
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this computer program that we ran in the last tutorial so if you remember
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whenever we first created a project in code blocks
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Code Blocks already made a very simple computer program for us to run and test out
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just to make sure everything was working and all that it was it printed out hello
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world
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on the screen. So if you go ahead and build and run this we see that
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it just says hello world and some other computer stuff that 
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isn't really relevant. But anyways all this computer program does
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is print out hello world and before I get into breaking this apart and telling you
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what each piece does I want to say one thing you would
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think since computer programs are just made up of a bunch of lines of text
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that we can learn each line
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one at a time but computer programs are weird in
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that this is pretty much the most simple program you can write and check it out
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there are already 7 different lines
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included here so in order to even really most basic program
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you need to code at least seven lines of code. So it seems kinda confusing and I just wanna
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just give you guys a warning. As long as you can get through this video
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all the rest the videos are going to be incredibly easy
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this is the only one where have to throw a bunch information at you
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but so, I'm gonna break it down is easy as possible.
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Uh, and the reason for that is because you need so many things in order to run
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such a simple program
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but once you understand the basics everything else is just smooth sailing. I
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promise.
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So, let me go ahead and we're gonna be getting more in-depth
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each of these lines. But, for now let me give you guys a brief introduction
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to what each line does. Let's go ahead and get started talking and work our way down.
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This include iostream line right here,
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this is technically called a pre processor directive. So, you you are taking a
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test to be watching these
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tutorials because you know maybe you're in C plus plus class and
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your teachers kinda confusing you. Answer on the test
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this is a preprocessor directive. Now what that means and
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everyday terms is it pretty much says alright
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we're going to be including a file in this program that we're going to be
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using later on
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so it's gon be including a file iostream
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that we didn't make. we didn't make this file, but it needs it to run this program
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later on. So that's why
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you needed to include it. Again we're going to be talking more about header files
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later on but
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for the basics of this tutorial, all you need is that
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to know that this line includes a file that our program needs to use
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later on. Now, the next line you can see
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is just a blank line. You may say alright "Do you need this blank line Do younot need it?"
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like lines and spaces you can have a million of them if you want
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or we can have none of them just like that. all blank lines do in programming
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is they make the program easier to read. So just as a book or magazine
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our newspaper sometimes you want blank lines between your code.
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Sometimes you just might go right under each other. It's personal
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preference.
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Um, people you know whatever you want blank lines just make it easier to read
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so whatever's easier for you
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at as many lines or less lines as you want. And that brings me to another point
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these tabs too. see this is kinda tabbed out or tabbed in and
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it's the same thing some people tap things and make easy read
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this program just gonna run just fine if it's just like that
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but you know people just like the line certain things up so you'll see later on
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once we get coding
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that taps and spaces and blank lines they don't really mean
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anything significant they just make the program easier to read so that being
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said
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under that link line is this: "using namespace STD"
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and believe me it on this does not stand for sexually transmitted disease.
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I like to think that, but trust me doesn't. It stands for the standard
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library and that's another thing that is built into
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C plus plus. That is pretty much same as we're going to be using
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all the standard things with C plus plus. Nothing fancy. Again,
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we're going to be going over libraries and stuff in the future but
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basically these two lines include things that we will need later on. This includes file
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in this includes something called a library. What you know.
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It is just a bunch of C plus plus stuff. So, with that being said we know that these
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two lines
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include things. fair enough. so now let's get to the meat
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and, I guess, meat and potatoes I guess other
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computer programming and that's this. this entire thing
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is called a function. now of computer programs
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are made up a functions and all functions are are
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things you want the computer to do. for example whenever we're making programs
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later on.
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We're going to make a function to play sounds and we're gonna make a function
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to draw graphics on the screen
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and as you can see functions are just things that you want the computer
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to do. So every computer program
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starts with a function called "main" this is how your computer knows
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where to start. So for example, in couple tutorials we're going to have a function
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called main
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and like I said we're going to have another function called
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"play a sound" and are going to have another function called "make a ball"
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bounce around on screen
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and you going to have all these functions and your computers going to say alright.
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You me all the stuff to do but how do I know order to do them in?
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Well your computer automatically knows
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anytime it runs a program to start with the main
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function so that's why it's so crucial to name this function main.
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So, in order to make a function you do this. You first write
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what type of data you're going to be working with
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and  functions typically do is
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to do some sort of calculations, for example find body mass index or
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calculate the velocity or something, well whatever makes his calculation
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it usually wants a number back, an answer in other words.
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Well since we're going to working with just integers, main always
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works with integers. so that's why we need that but again we'll be getting into
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that later on
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after that is the name up the function in this one is named main
Um, don't worry about these parenthesis right now but what we do need to worry
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about
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is these little..., are a semi colons
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squiggly brackets, ugh, I guess work out curly braces
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I don't know whatever the heck they are.In this
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has an opening and closing curly brace and in between on
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you have something called statements. now all functions are made up of statements
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and all statements are basically instructions
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and each instruction needs to end with a semicolon. that's why you
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every line inside a function ends with a semi-colon.
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for example if you had a function that says
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make peanut butter jelly sandwich one statement would be
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get out bread, the next a man would be put butter on a piece of bread. the next statement
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would be put jelly on piece of bread.
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The next putting together. the last put them in your mouth.
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BAM. you now have a function and a series of statements.
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well all this function did. the main one said, perhaps something on screen
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and return 0. Simple enough, so now you can see the basics a function
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how they're made in how every function needs to include
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statements or instructions. So, that being said, let's break this down
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even more. the first statement is saying this.
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first from the COUT thing right here. That's called an output
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stream object and it's basically used to write characters on the computer screen.
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that's how we are able to type hello world on the computer screen.
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so this is always used in conjunction with this.
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this is called the stream insertion operator. This pretty much takes all the
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stuff to the right of it,
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and print it out on-screen. I mean this is
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just saw. you know it's weird symbols but
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that's ok whoever made C plus plus they decide to use these were symbols
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to print out something on screen. why they did that, you have to take it up with
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them
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by anyways this is basically how you pronounce up in screen
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so this prints out hello world and then
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this pretty much just means END line, or go to the next line.
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so this line right here is pretty much the same print something on the screen
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now this last thing I want to talk to you guys about is called
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the return statement. now usually like I said
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functions will calculate something like body mass index or velocity
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and when they calculate it, it's going to want an answer back. so,
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if I had a function that calculated my weight, it would return
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155 or 160 depending on if I ate tacos or not today.
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well the main function should always have
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return 0 and return 0 means
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whenever you return 0, it tells your program that it ran fine without any
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errors
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for example if he had a buncha actually text right here. your computer program
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would give you an error.
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and it would never get to this line right here so and never return 0
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so whenever it does get to this line, it means everything above it
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ran fine. in return 0 means your good to go.
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main ran fine. so I know that was a lot of information
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to get you guys for just your first tutorial, but again like I said,
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every computer program starts with a buncha stuff that you need to know.
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And we are going to be covering each more the topics in depth but for now I just want
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to give you guys a basic understanding
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of how a computer program is made. so if you don't understand everything completely
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then don't worry
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you're not alone you will in future, I promise. But for now
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thank you for sticking with me and I thank you for watching this tutorial. 
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and I can't wait see you next tutorial. and if you have any questions
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forget to check out my website the newboston and com and
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yeah are seen next video