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What is a programming language.

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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.

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We give it an instruction manual and the computer follows without code.

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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 you wouldn't be able to play Pokemon on your phone 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 well they speak in ones and zeros all electronics speak that language

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of on or off zero or 1 but writing ones and zeros would be gibberish for us.

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It's hard for us to communicate like that.

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Right.

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So humans have developed 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 they're closer to machine language and other programming languages are higher level than others.

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That is they're closer to English or a human language and there are lots of programming languages.

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You have languages like assembly that is really really 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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That's great.

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We have these pieces.

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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 Web site show us a display of all our flights telling the computer to show those

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flight information on our screen 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 maybe

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even Java.

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And then we somehow need to get these files that we write into ones in zero so that the our machines

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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.

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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 and

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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 a nother program written by a human it can either be an interpreter or a compiler.

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Now Python usually uses an interpreter usually an interpreter.

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Just like a translator goes line by line through our code and executes our code on our machine.

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Compilers are a little bit different.

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They take your code all at once read the entire file all at once and then translate that to machine

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code.

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So again interpreter goes line by line and each line executes an instruction a compilers takes the entire

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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 but I want you to just have this general picture

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that when we write code whether it's Python JavaScript Java C or C++ what we're doing is we're typing

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it in a language that is human readable.

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We're giving it to one of these translators like an interpreter or a compiler.

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And these spit out code that are able to run on our machines so to review interpreters translate.

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Line by line and execute the line before going to the next line compilers translate all lines of a program

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to a file usually called a binary and execute the whole file at once now in the next video we're going

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to talk about this process a little bit more in detail especially on how it works with python.

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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 if you work right now to your computer and let's say you opened up a text file like this one and

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

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for Pokemon 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 in order

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for us to start writing Python.

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We need to download this translation service in the next video I'm going to show you how to do that.

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I'll see in that one.