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Welcome back.

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Let's talk about our next data type.

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And it's a big one.

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A very, very useful one.

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It's called List.

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And list is an ordered sequence of objects that can be of any type.

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So you can think of them as strengths, right?

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We had strengths previously that we learned about, except that each sequence of this string, well,

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was was a string was a letter or a number wrapped in quotation marks.

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Lists, on the other hand, looks something like this.

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Let's say we create a variable ally and lists we denote with square brackets.

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And inside of the square brackets we can have different objects.

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So for example, we can have one, two, three, four, five.

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We can also have, let's say, Ali two.

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And this is going to have a.

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Be.

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See.

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And it can have any collection of items that we want.

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We can even mix and match and say that we have one too.

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Then a then maybe even the boolean value.

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True.

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So all of these are lists.

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Now lists are extremely important and in other programming languages you might have heard the word arrays.

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So in Python lists are a form of array.

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And later on when we get into the modules section of the course, we will talk about the difference

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between lists and erase.

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But if you are coming from a different programming background, then lists are like arrays in your language.

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A collection of items.

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Now, the neat thing about lists is that it's the first data structure that we're learning.

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Now, what is a data structure?

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Data structure is a very important concept in programming languages.

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It's a way for us to organize information and data into, let's say, a folder or a cupboard or a box

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so that these data structures can be used with different pros and cons.

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For example, you have a fridge where you store your food, and fridges are really, really good at

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putting your food inside, keeping it cold, and then taking it out.

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Or you might have a backpack.

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A backpack is really, really good to stuff everything in there.

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But when you're looking for things in a backpack, it's really, really hard.

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So you can think of data structures similar to that, a container around your data that has different

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pros and cons of accessing that data, removing that data, writing data.

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But that's something we'll get into a little bit later.

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The key here is that the square brackets allow us to contain information and data like strings, integers,

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floats if we want to booleans into a contained fashion.

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So let's think of a good example here.

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What if we had a shopping cart?

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Let's say we're Amazon here, and then Amazon has the Amazon shopping cart.

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And in here we can collect different things that we want.

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Maybe we collect some, I don't know, notebooks.

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And you know what?

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Let's get some gadgets.

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Let's get some maybe some sunglasses.

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We can add different items here, different strings, different data into this cart.

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And now, just like we saw in strings, we can access the Amazon cart in different ways.

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For example, I can access it again with square brackets and simply say I want to item zero.

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So if I print here.

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And do Amazon cart.

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Look at that.

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I get notebooks.

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The second item.

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I get sunglasses?

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What about the third item?

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Nope.

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Lyst index out of range.

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But this should make sense now.

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This is a list where we're accessing the index of.

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But it only contains two items.

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So if we're going zero one to the third item, nothing exists.

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So our program says that doesn't work.

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You're doing something wrong.

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And just like strengths, these list items are in memory in their separate bookshelf.

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Right?

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But one right next to each other.

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So we can go zero one, two, three, four, five, so on and so forth until the list ends.

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All right.

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Let's learn about lists.

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A lot more in the next video.

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Bye bye.