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Hey, everyone, in this video, we are going to talk about something super cool, which is date and

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time in JavaScript, we can easily work with date and time using the date glass.

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Don't worry about understanding what a class is right now, although if you want, you can just go to

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Google and search for jazz classes.

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Then you have a lot of things to read.

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So you can understand better what classes are for now, just think of classes as an object, they are

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actually more than this.

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They are actually like a template for objects.

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But for now, just think of the date as an object which will have properties and methods and everything

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we've been working so far.

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So to create an object with this class, we need to use the new keyword.

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So that's the difference between a regular object and a class.

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This time we need to use the new keyword, so let's create a new variable.

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Actually, let's do an individual story called.

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Let me just copy this.

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So I'm just creating a variable.

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And I'm using the new keyword, and then I'm just using date opening and closing parentheses, so this

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means that I'm creating an object of the date class.

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So now let's just do console that log so we can see what's inside this object.

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So refreshing the page, as you can see, this is returning the date and time I'm recording this video.

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Now, just out of curiosity, let's do type of.

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And then Beit.

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Object, so, as you can see, this is just a regular object.

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But this is super cool because it just returned the current time and this is like the full version of

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the date.

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So as you can see, we have week, day, month, day, year, hours, minutes, seconds.

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Then we have the time zone and then the information about daylight saving time.

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So this is the complete date.

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And if you want, you can also get specific information.

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So let's say you just want to get the year what you can do.

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It's just to date.

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O'Bagy and then you can use a method called Get.

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Full year.

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So if you do this, then, as you can see, you are just going to get the ear back.

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So in this table you can see some more examples so you can get to be extra careful with this, because

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as you can see, the mouths, they start from zero to 11.

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So it's not from one to 12 like we are used to work with mouths is the only thing you just need to pay

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attention to.

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So for the rest here, there's nothing new.

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So for the hours we have it from zero to twenty three.

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We have minutes.

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Seconds.

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Milliseconds, then there's something cool here that is the get time method's let's try to do this so

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they Tobji instead of using the get foliar, let's use the get time method.

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So as you can see, we are getting a big number.

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So what is this?

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This is the number of milliseconds since the epoch, which is January 1st, 1970.

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So JavaScript uses the Unix epoch.

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Every programming language has an apoc, which is used to set the starting point of counting time,

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so this is useful to do calculations with date and time.

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So like I said, the Unix epoch, which is used by JavaScript, is January 1st, nineteen seventy zero

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zero zero UTC time.

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So this does not mean that we can't work with dates prior to 1970.

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We can do it.

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We're just going to have negative numbers.

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So anything after nineteen seventy, then we will have this positive number of milliseconds, so this

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is the number of milliseconds that have passed since the book.

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So now why is this useful?

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Why do we need a starting point to have this number of milliseconds?

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Because when we work with this, which is actually called a time stamp, so every time we work with

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milliseconds since the APOC, we can call it time stamp.

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And when we are working with time stamps, we have more flexibility to easily do calculations with dates.

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So if we want to get how many years have passed since the apoc, this is pretty simple to do because

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we have the number of milliseconds, then we just need to know how many milliseconds we have in one

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ear.

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So here.

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I have this table, so I know that one year has this number of milliseconds, so if I get all this number.

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And I just divided by the number of milliseconds in one year.

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We can see that this is something close to 50, which is accurate because I'm recording this video in

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2020, so from 1970 to 2020, we have 50 years.

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This has that because I'm in the middle of the year.

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So if I just want to get the number of years I could do like this and then just use the math.

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That floor, which is going to round number, is down.

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So now I know that 50 years have passed since the epic.

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And I know that maybe it's not very useful to get how many years since the apoc, but this is going

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to be useful to compare to different dates.

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So let's do a few tests with this.

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But first, let me teach you how to create specific dates, because so far we just created a new date

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object and we did not pass any argument.

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And when we do this, it just creates an object with the current date and time.

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But we can also use something specific.

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So if you want to create a specific date, you can pass from one to six argument.

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So let me just clear this real quick and now.

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Let's do a few tests, so I'm just going to do a new date again, and if we do this, we can see that

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it's creating this object with the current date and time.

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But let's try to use one numeric argument.

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So if we use just one, it's the millisecond since the apoc.

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So let's just get the number of milliseconds in one year just so we can see how this works.

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So if we do this, we can see that we created a date in 1971, which is exactly one year after the APOC,

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so here we can also use a different number of arguments.

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So if you use two numeric arguments, it is just going to consider it to be year and month.

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So let's try again with two arguments.

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So the year let's try, I don't know, 2010 and then the month.

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Don't forget that the month they go from zero to 11.

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So if I do this, as you can see, January 2010.

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Then we can do the same thing with three arguments, four or five up to six, you can read.

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All the details here.

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We can also bass strings as arguments in three different formats.

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So if we create this object and we pass the ISO date.

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Which is formed by the full year, so 2010, let's say, then two digits for the month, then it's like

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we know it's like January, it's just zero one.

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And then the day, let's say 18.

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As you can see, we just created a specific date.

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We can also use the short date, which is written like this or month day in here.

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And we can use the long date as well.

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Which is going to work like this, so April is going to be a PR April 10th.

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Two thousand and twenty two.

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So here you go.

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We just created this object, and now that we have this object, we can get any information we want

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from it so we can get the number of milliseconds since the Abuk, which is useful to do calculations,

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we can get specific information like just the month or the hours or minutes.

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So how can we use all this in a useful way?

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So there will be two very nice examples and one of them is going to be the challenge for this lesson.

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I want you to calculate date intervals.

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So let's say we have a product that was ordered on March 26, 2020, and it was delivered on April 2nd

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to 2020.

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I want you to use date object to calculate how many days does it take this product to be delivered.

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So just calculate this using date objects and show the number of days here.

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Just take your time, try to solve this.

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And in the next video, I'm going to fix this.

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And in the next lesson, we are going to talk about time methods in JavaScript and there will be another

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very cool challenge for you to do.

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So I'll see you in the next video.