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Welcome back.

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Let's talk about our next data type, and it's a big one, 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 string's, right?

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

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

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Lists, on the other hand, looks something like this, let's say we create a variable ally and list

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we denote with square brackets and inside of these 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 like two.

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And this is going to have a.

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See, and it can have any collection of items that we want, we can even mix and match and say that

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we have one, two, 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

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word or phrase.

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So in Python lists are a form of Arae and later on, when we get into the modules section of the course,

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we will talk about the difference between lists and arrays.

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

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A collection of items now the neat thing about lists is that it's the first data structure that we're

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learning now, what is a data structure?

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Data structure is a very important concept and 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 putting

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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.

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Different strengths, different data into this cart.

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And now, just like we saw in String's, we can access the Amazon card 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, so if

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I print here.

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And do Amazon cart.

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Look at that, I get notebook's the second item.

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I get sunglasses.

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What about the third item?

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NOC list index out of range.

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But this should make sense now, this is a list where we're accessing the index of.

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But it only contains two items, 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 strings, these list items are in memory in their separate bookshelf, right, but one

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right next to each other so we can go zero, one, two, three, four or five, so on and so forth until

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the list ends.

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All right.

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Let's learn about lists a lot more in the next video.

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Bye.