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Javascript is a dynamic, interpreted programming language but it's also a weakly typed programming language.

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Now what does this mean?

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For one, the dynamic interpreted part as you learned means that it's not pre-compiled, other languages like

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C++ are compiled during or after development,

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so before you share them with the end users, Javascript is on-the-fly compiled and that means that the

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code is evaluated and executed at runtime,

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it also means that the code can change at runtime.

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Now of course not the code you wrote and it won't magically change, of course the code you wrote gets executed

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but in that code, you can do some things which you are not allowed to do in other programming languages,

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for example if you're working with a variable, something we will only learn in the second module,

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for now you can just keep in mind that a variable is a data container,

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you might store let's say some text in there, text you need in your script to for example output it to

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the user. In Javascript you are allowed to dynamically switch the type of data there. In a variable, you

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might start by storing some text and suddenly at a later point of time, you store a number in there instead,

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in the same variable.

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Now again, we haven't really learned about variables yet,

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we will of course do that but the one thing you can simply keep in mind is that the dynamic thing in

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Javascript means that it is parsed and interpreted and compiled at runtime and that therefore it is

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able to do certain things,

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for example switching the data of a variable other programming languages are not allowed to do.

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Now it's not necessarily good to switch the type of data dynamically or unexpectedly but you can do

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that,

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the main takeaway however is the on-the-fly compilation and interpretation. Now what about the weakly

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typed part here?

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This means that when we work with data in Javascript, for example text data or numbers, you don't have

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to tell Javascript that you're going to work with a text now or you're going to work with a number now,

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instead

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data types are assumed, are inferred automatically so to say, that's also related to this dynamic

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nature where data types can also change from one line to another.

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Now this might sound strange but in other programming languages, you have to define the type of data

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a variable will hold in advance. In Javascript, that's not the case, you don't have to tell Javascript

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that this variable, this data container will hold a number, instead you store a data in there and if that

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happens to be a number, so it is. In other programming languages, you have to tell the language that you're

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going to store a number in there

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and if you store something else, you would get an error.

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That's not the case in Javascript, it's forgiving there because it's dynamic and it also doesn't care

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about strong type definitions in advance,

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instead you just store data in there and go with every type of data that holds. So data types are not

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set in stone but can change.

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Now this is arguably a bit more advanced,

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I just want you to be aware of these terms, dynamic and weakly typed right now and they will make more

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and more sense as we progress throughout this course and work with data and variables.

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For now, just be aware of these terms.