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Now let me get rid of that existing code,

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you find a snapshot of the code we wrote thus far attached to the last lecture and

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let me write some new code.

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An important thing you work with or important data structure you work with in javascript are objects.

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You could have something like the person object and you create an object typically with curly braces

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and then in there, you have key value pairs.

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You define the key by simply typing, well whichever key you want to use, let's say name

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then you have a colon, you must have the colon and after the colon,

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you have your value,

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in my case a string Max and then with a comma, you can add another key value pair,

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age 29.

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Now this is an object and I can log person here, if I now execute play.js, we see that object being

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printed here.

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Now objects allow us to group data together,

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you can also not just have variables in there so to say but you can also have functions in there,

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for example a greet function and there you can simply have an anonymous arrow function or an arrow function

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general as a value after the colon and then in there, you could have console log

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Hi I am

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and then the name and this would now be accessed with the this keyword, instead of an object you have

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to use this to

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typically and there is something special about this which I showed in that video I linked before

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in an earlier lecture

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but typically this refers to the surrounding object

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and now we can use the dot notation,

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so dot to access properties or methods,

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so variables or functions inside of that object,

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so we could now use this name.

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And now I can use that person and call greet with the dot notation and executing it as a function,

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so the dot notation is important on this which refers to the object or on you, referring to that object

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which is stored in this constant here. And now if I execute this again, I'm saying hey I'm undefined,

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now why is that?

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Well the reason for that indeed is what I talked here about arrow functions.

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This now here refers to the global scope, to the global node runtime scope and not to this object, to

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have it refer to that,

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we either have to use the old school function, like this. Now if I repeat that, I'm saying Hey I'm Max or

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we use a slightly different approach or syntax here in an object

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and that is you don't use an arrow function but you use greet like that.

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So you omit the colon, add the parentheses after the key name and then without a function keyword or

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anything like that, you add your function body

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and now this is a method of this object

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and you see

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Hi I'm Max too now.

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So this is something important and this is the syntax you'll see me use throughout this course, without the colon

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parentheses right after the key and then the function body.