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What is a programming language if someone asked you this question, can you answer it?

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Programming is simply a way for us to give instructions to computers, we give it an instruction manual

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and the computer follows without code, computer programs wouldn't do anything.

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You wouldn't be able to move the mouse around on your screen.

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You wouldn't be able to Google things.

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You wouldn't be able to play Pokemon on your phone.

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Right.

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I can't just tell my computer what to do.

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You see, computers don't understand English or any other human language for that matter.

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So what language do computers speak?

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Well, they speak in ones and zeros.

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All electronics speak that language of on or off, zero or one.

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But writing ones and zeros would be gibberish for us, it's hard for us to communicate like that, right?

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So humans have devolved programming languages that are in between human language and machine language

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that is zeros and one some programming languages are lower level than others.

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That is there closer to machine language and other programming languages are higher level than others

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that is there closer to English or a human language.

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And there are lots of programming languages, you have languages like assembly that is really, really

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close to machine code.

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You have languages like Python and JavaScript that are really, really close to English.

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OK, that's great, we have these pieces, but what are we missing here?

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I mean, if I want to find flights to Hawaii, how do we go from here to.

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Well, having, let's say, a website, show us a display of all our flights telling the computer to

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show those flight information on our screen.

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What are we missing here?

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Well, we have these programming languages that we usually write on a file such as Python, JavaScript,

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maybe even Java, and then we somehow need to get these files that we write into ones and zeros so that

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the our machines can understand.

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Well, we need a translator, right?

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We take our code that we write what we call a source code written in a programming languages, and we

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give that to a translator that can understand that language but also understands machine language.

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And this translator just translates these files for us.

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So what is this translator, it's not really a person, right?

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I'm not giving my code to somebody and somebody is going to just start shouting at the computer that

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be quite silly.

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What is this translator ready to have your mind blown?

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Well, it's another program written by a human.

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It can either be an interpreter or a compiler now.

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Python usually uses an interpreter usually.

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And an interpreter, just like a translator, goes line by line through our code and executes our code

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on our machine.

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Compilers are a little bit different.

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They take your code all at once with the entire file all at once and then translates that to machine.

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So again, interpretor goes line by line and each line executes an instruction.

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A compiler takes the entire file and turns it into machine code.

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Now, the differences between these two are a little complicated and beyond the scope of the course.

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And don't worry, we're going to come back to this topic.

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But I want you to just have this general picture that when we write code, whether it's Python, JavaScript,

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Java, C or C++.

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What we're doing is we're typing it in a language that is human readable, we're giving it to one of

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these translators like an interpreter or a compiler, and these spit out code that are able to run on

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our machines.

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So to review interpreters, translate line by line and execute the line before going to the next line,

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compilers translate all lines of a program to a file usually called a binary and execute the whole file

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at once.

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Now, in the next video, we're going to talk about this process a little bit more in detail, especially

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on how it works with Python, but why did I start with this?

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I mean, this is a complex topic.

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Most developers, especially if they're starting out, don't even know of this process.

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They just know that they write code and then it runs.

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So why did I teach this here?

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Because in order for us to be able to write Python code, well, I can't just write it anywhere.

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Right.

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If you went right now to your computer and let's say you opened up a text file like this one.

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And you started typing Python code, but for now we don't know Python, so let's just say I want to

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go search for Pokemon.

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Well, this might be code, we don't know if it is, but I can't just use this right.

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I mean, this isn't really python code, but how would my computer know what I'm talking about?

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In order for us to start writing Python, we need to download this translation service.

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And in the next video, I'm going to show you how to do that.

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I'll see in that one.