And my name is Sean.

Over the next 90 minutes, we'll be taking you through this series consisting of 21 different

segments that hope to cover the basics of computer programming, which can apply to any

and all programming languages you might want to learn. We'll be starting with the simplest

question of what is programming, and from there will be working our way up as we talk

about common features of computer science such as loops and arrays. We'll discuss

how to read and write code, debug code you've written, some strategies to help plan out

your code, and much, much more. The complete list of topics that are going to be covered

in this lecture-style video are shown on the screen now. Additionally, there will be time-stamps

in the description, so feel free to skip around if you are already proficient in some areas

of computer science, or just want to know about a specific topic we will be covering.

Hopefully, by the end of the series, you'll have a basic understanding of what computer

science is, along with an armory of useful skills that will help you unravel whichever

programming language you decide to learn first.

We'll only be covering the major key points that apply to all programming languages, so

we'll be shying away from topics such as object-oriented coding and command line navigation,

as those are things which are language-specific. Additionally, there will be no software required

for you to download in order to follow along with this tutorial as we won't be writing

any code to keep things simple and concentrated. This video is meant for those who are interested

in computer science and programming but have no idea where to start and have little to

no background information on coding, and so if that sounds like you, then strap Sean and

I work our way through the wacky world of computer science, starting with the biggest

question probably on your mind, which is what even is programming?

Well, the dictionary defines it as the process of preparing an instructional program for

a device, but that's a really confusing definition, so in layman's terms what exactly

does that mean? Essentially, it is attempting to get a computer to complete a specific task

without making mistakes.

Imagine this, for example: you want your less-than-intelligent friend to build a lego set, except he has

lost the instructions and can only build based on your command. Remember though, your friend

is far from competent, and so If they are not given very specific instructions on how

to build the set, there are many mistakes he could make. If he thinks like a computer,

then if there is even one piece that you have not told him specifically where to place and

how to place it, the entire lego set will be ruined and he will be left to suffer a

complete mental breakdown causing the whole goal of the project to be corrupted. Giving

instructions to your friend is very similar to how programmers code. Instead of a less-than-intelligent

friend, you have a less-than-intelligent computer, and instead of instructions on how to build

a lego set, we are feeding it information on how to complete a program like a game or

web application. An important thing to note is that comptuers are actually very dumb.

We build them up to be this super sophisticated piece of technology, when in actuality, a

computer's main functionality comes from how we manipulate it to serve our needs.

Now, programming isn't as simple as giving your friend instructions since in a programmers

case, the computer doesn't speak the same language as you, the computer only understands

machine code, which is a numerical language known as binary that is designed so that the

computer can quickly read it and carry out its instructions. Every instruction fed to

the computer is converted into a string of 1's and 0's and then interpreted by the

computer to carry out a task.

Going back to the lego example, this process would be like if he was not only less-than-intelligent,

but to make matters worse, he could not understand english and only speaks in mandarin chinese.

In order to speak with him, you have to convert the instructions that you understand in english

into the language that your friend understands. This process is essentially what you must

do for your computer in order to make it understand the instructions you give it.

The big difference between the two examples, however, is that it is very difficult for

people to understand machine code and binary. Directly translating what you want the computer

to do into machine code is extremely difficult, in fact almost impossible, and would take

a very long time to do if you could. Each program is composed of millions upon millions

of those 1's and 0's, so how, exactly, are we supposed to translate our instructions

into machine code?

This is where programming languages come into play. Programming languages are fundamentally

a middle man for translating a program into machine code. These languages are much easier

for humans to learn than machine code, and are thus very useful for programmers. Going

back to our lego example, a programming language would be sort of like an interpreter, that's

able to take the instructions you give them in english, and translate them into instructions

your non-english speaking friend can understand. This makes programming languages extremely

useful and the backbone of almost any good program. Think of programming languages as

not english, and not machine code, but somewhere in the middle.

There are many different programming languages out there that each have their own unique

uses. Languages such as Python and Java act as general purpose languages that can perform

a variety of computational tasks, while RobotC or HTML/CSS are languages designed for more

specific purposes such as moving a robot or constructing a website. Languages can also

vary in how powerful they are. For instance, JavaScript is a scripting language that is

designed for smaller tasks while java or python can carry out much more computationally taxing

processes.

We measure a programming language's power, or level, by how similar it is to machine

code, the series of 0's and 1's we talked about earlier. Low-level programming languages

such as assembly or C are closer to binary than a high-level programming language such

as Java or python.

The basic idea is that the lower the level of your programming language, the more your

code will resemble what the machine can interpret as instructions. Aside from the different

purposes that each language fulfills, choosing a programming language typically comes down

to a matter of preference, as there are usually many languages that accomplish similar tasks.

Try different languages, and decide which one's rules, interface, and level of simplification

you like best.

So now that we know what programming is, how do we actually write code? It's not like

we can simply type words into a text document and automatically assume that the computer

can translate it into machine code, read it, and carry out a task like opening up a browser.

And additionally, we can't just write down rubbish in certain programming languages mentioned

in the previous episode and expect the computer to understand. So how are we supposed to write

code then?

Well, the answer is with an IDE. An IDE, which stands for Integrated Development Environment,

allows the facilitation of code by a computer. IDE's provide a graphic interface on your

computer in which the programmer can easily write, run, and debug code without having

to worry about problems with compilation or interpretation of the program. Think of an

IDE as any other program on your computer such as a game, a browser, or even the file

explorer, except we'll be using it to write code. IDE's are able to turn your code into

machine code and run it through the computer to produce results.

In addition to providing a place for programmers to develop their code, IDE's provide some

extremely useful tools for programmers to ease the job of writing code, such as built-in

error checking because as we'll talk about later; code doesn't always run correctly,

auto-fill in for frequently used words or phrases, and project hierarchy which will

help you organize and manipulate the files within your project. Back in the olden-days,

before IDE's, code used to be written on punch cards and then fed into computers which

would take hours and cause a lot of pain. IDE's nowadays act as a sort of fast-track

to writing code and make things a whole lot easier for programmers. An example of a specific

IDE can be seen on your screen now. In the center you can see the program that is currently

being written, and right below it the console, which can print out useful information for

the programmer. This specific IDE is used to write java code. IDE's are extremely

powerful and will be used in almost 100% of your programming projects.

So through these IDE's we are finally able to write and compile code smoothly without

worrying about the computer not being able to understand it. The next problem we run

into then becomes how do we write this code in the IDE, because it's not like we can

just type random words from a certain programming language and expect the compiler to understand

it. This is where a programming language's syntax comes into play.

Now, just as if you were learning a real language, learning a computer language can be very similar.

Some have different styles that may seem odd, some may make you use abstract or weird concepts

which may be confusing, and like all languages, programming languages have a set of rules

that you must follow when writing code in that language, and at the forefront of those

rules is grammar. Programming grammar is referred to as syntax and is very similar to real-world

grammar. Each programming language has its own syntax, or rules, that you have to follow

to a tee if you want your program to run correctly, just as if you were speaking in real life.

These can be things such as how you type out certain functions, what you put at the end

of a line of code, and how you set up certain functions. Each language is unique in its

syntax, and while some may share similar rules, all will have some quirk which makes it stand

out from the rest. Syntax is something that catches a lot of people off guard, since many

expect every programming language to follow the same set of rules, but as we spoke about

in the last segment, because each language is specialized for a specific task, each needs

its own set of rules to function. Breaking or disregarding these rules will result in

an error, just how breaking or disregarding rules in real life will result in an unintended

message.

As an example. If we wanted to do something simple such as initialize a variable, which

is something we haven't covered yet but the example is still relevant. In java, you'll

notice we have to specify what type of variable we are defining in this case an integer, and

also add a semi-colon after the statement. In python, we don't even need to define

that we are trying to create a variable and just have to type what we want to create,

and in javascript, we just specify we are making a variable, but do not include what

type of variable we want to make. Even in this simple example you can see how much syntax

matters when learning a new language since while the goal of our program remained the

same, define an integer with value three, all the programming language shown took different

approaches. All these languages require that you follow this syntax because remember, computers

are extremely dumb, if you forget one semicolon or misplace a character, the entire program

will not run and send you back a syntax error, which is something we will talk about later.

Think of this as if you forget a comma in a sentence and the entire context of what

you are trying to say get misinterpreted. For example, in the sentence “let's eat,

grandma”. If you were to forget that comma, while it may seem like a small mistake, it

changes the entire context of the sentence, making it sound like you're about to eat

your grandma. The same rules follow for programming, if you forget a semicolon, the entire context

of your program could be corrupted and misinterpreted.

Now another thing which makes IDE's so useful is that they will let you know if and when

there are syntax errors in your code. Syntax errors of course being parts of your code

which do not follow the rules we talked about previously. The IDE will tell you where in

your code the error is, and also won't let you run your program until the error has been

fixed. Because of how important syntax is to writing code and learning a new language,

it's recommended that you learn the rules and syntax of a language before beginning

to write complex programs in that language. Most of the rules are tedious to learn but

easy to master and as soon as you can do that, you'll be able to easily identify syntax

errors and take care of them easily.

That covers the basic gist of syntax and programming rules, so now that we know HOW to write code,

and WHERE to write code, we next need to cover what happens after we have typed out our program

and run our code. Because writing a piece of code for a game or for a database is cool

and all, but after the computer interprets the program, how will we know what's happening,

and whether it is working or not? Well, programmers do this by looking at the console. The console

is a text interface within the computer that us programmers can use for a variety of different

purposes. If you remember, a short while ago we showed a picture of a basic IDE, and one

of the main parts of that picture was the console.

The main use of the console is to output text from the program. This is usually done using

a print statement. A print statement is a command that does exactly what it sounds like:

it prints text to the console. This print statement is the first piece of ACTUAL CODE

we've talked about in this series, and it's about as simple as it gets. The print statement,

despite its simplicity, is one of the most important functions in programming and exists

in some form in just about every programming language.

The most basic thing you can ask the print statement to do is just simply make it say

something. This is done by instructing the console to print, and then include whatever

you want to be printed inside the parentheses. For example, in python, the segment of code

print(“Hello World”) will cause a message reading “hello world” to appear onto the

console. Pretty neat.

The print statement is also vital for viewing and interpreting the computer's output from

a program. For instance, if you tell a computer to run a simple calculation, for instance

to determine what 4+3 is, it will run the program internally and compute an answer.

However, what is the purpose of having the computer run this program if you will not

be able to tell what the result is? Instead of simply telling the computer to perform

this calculation, instruct the computer to print the output of the program to the console,

and upon the program's completion, 7 will appear on the console. As you can see, the

console allows us to easily print information out to the developer for a variety of uses.

It is important to note that the print statement varies depending on the programming language

being used. For example, in Java there are multiple versions of the print statement depending

upon whether you would like a line break after the printed text, and specialized print statements

which make your code more efficient. Also, the general syntax of using a print statement

and certain nuances of its function can change between languages. However, you can generally

rely on it carrying out the same overall function, as it is a foundational statement for programming

in general. So print statements, they print information out to the console for the developer