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Arrays are a very useful data type,

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a very useful kind of value for

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storing related data

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that can be expressed as a list of data.

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Basically, just as we had lists in HTML

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you could say for outputting related list data.

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Sometimes we also have other kinds of related data

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which is not just a list

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but which

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is related,

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but needs more context,

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so which is not just a list of equal values;

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these are all hobbies after all

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but instead multiple connected values

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that describe different things.

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Sounds very abstract.

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Let's consider a passport or an ID.

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This here,

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for example, is the German

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ID,

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but you have something like this for

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every country in the world, I would assume.

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And the interesting thing here is that

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this of course describes related data in the end,

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but we have labels that tell us

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which piece of data

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describes which trait of this person.

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So for example,

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we have a label for the name and then we have to value

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the actual name of this person.

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Last name and the first name,

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we have to date of birth and so on.

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And we always have these labels

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and then the values for these labels.

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And overall,

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of course,

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we can clearly say that this is related data,

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all these different pieces of data,

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describe one person,

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but it's not a list of data because

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it's not the same kind of data.

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We have names,

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dates,

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countries,

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cities,

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different kinds of data on there.

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So it's not the same as a list of hobbies

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and to describe such kind of data

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as well in JavaScript,

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we have another important data type,

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another important value we can create.

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And that would be objects.

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Let's say

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our

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user who visits this website has

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a job,

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but a job is not just a string where we say

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developer,

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for example,

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but instead,

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the job could be a combination of different values,

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where we have the name of the company,

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the place where he or she works and so on.

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And for that, we could create such an object.

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We do that with curly braces after this equal sign here.

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So opening and closing curly brace,

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and between those curly braces,

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we now put the different

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properties of this object,

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the different labels and their values,

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that make up, this overall object.

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And we call these label value combinations properties

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in the context of such a object in JavaScript.

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And these labels are up to us.

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And we could say that a job is described by a title

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and then maybe the place

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where this job is being done.

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And therefore we could add two labels here,

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a title label,

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and then separated by a comma,

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our

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place

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label.

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And again, these labels are up to you.

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You can use any labels you want.

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Now the labels on their own are not that useful though.

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If we have a look at our passport again,

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we did not just have the labels there,

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but also values for those labels

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and values are now assigned,

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not with an equal sign,

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but by a colon after our labels.

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And then after that colon,

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before you have that comma,

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and then the next label

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you have to value for that label

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and values for labels instead of an object.

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Can again be all those values you already learned about

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strings,

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numbers,

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arrays,

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even other objects.

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So-called nested objects,

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but that's something we'll explore later.

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So here,

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our title could be a string

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and that could be developer for example,

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and then place also needs a value.

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So we add a colon and then again,

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a value that makes sense here.

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So that could again be a string

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and it's maybe New York,

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maybe a job also has

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a Salary.

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And that could be a number let's say

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50,000

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U.S dollars per year

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or anything like that.

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That could be a job,

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a rich object where multiple pieces of data

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are grouped together.

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Now we could also use

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three individual variables.

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We could create a variable

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job

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title

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that store's developer

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and create another variable

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job

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place

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that store's New York,

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and create yet another variable

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job

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salary

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that store's the 50,000.

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We could use these three variables instead

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of this job object.

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We could work with a those of variables in our

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subsequent code as well,

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but

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if we use three individual variables,

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instead of one object,

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then we as a developer,

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always have to kind of keep in mind

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that these three variables are logically related.

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And that might be easy to do,

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especially in a simple script like this,

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but it's even easier if you grouped them together

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explicitly by creating such an object

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just as we created an array for

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multiple connected list items,

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instead of working with multiple variables.

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And that's why here I will not create

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three individual variables,

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but instead of one object that

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has these different properties,

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by the way,

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you can of course think about these properties as variables

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that are

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a scoped, that belong to one object.

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You don't have to let keyword here though.

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You just directly have to label name and then the value.

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And you assign that with a colon

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instead of an equal sign.

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But other than that,

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it's basically like variables

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that are

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closed

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into that object.

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So to say.