 Hi everyone, in this lesson, we're going to talk about built-in data structures in Python. In this lesson, we will not talk about what those structures are and when you need to use them and when you don't. In this lesson, we'll talk just about how you can define them and how you can populate them with elements and how you can call them. So, in Python programming language, there are four built-in data structures. First data structure is list. How can we define list? We'll say, for example, we'll make variable myList and we'll call Python's built-in function list, which will create an empty list and store it to myList. If we now try to call myList variable, we will notice that our list is empty and list is stored inside curly braces. If we want to populate our list with elements, we'll use that same brackets and we'll put inside those brackets any elements, for example, four, five, six and so on. If we want to call myList, then elements of that list will be printed to our idle. Now, second built-in data structure in Python is dictionary. Let's create one dictionary, for example, myDict equals and let's call built-in dictionary function dict. That will create an empty dictionary and let's store it into variable myDict. Let's say myDict. Let's show what we have now in an empty dictionary. An empty dictionary is represented by empty curly braces and if we want to populate our dictionary, we'll use that same curly braces and we'll put some elements inside it. For example, letter A is the first and letter B is the second, for example. That's a simple example with some random values. I pick up some random values and now let's see what we have into our myDict variable. Now myDict variable or dictionary is populated with those elements. Now, the third built-in data structure in Python is a set. Let's make one set, for example, mySet equals and let's call again built-in function set which creates an empty set and store it to variable mySet. If we call variable mySet without parentheses, we will see that in Python programming language emptySet is represented by value set with empty parentheses. It's a little bit strange but that's how creators of Python decided to make some symbol that represents an empty set. Okay, let's populate our set. We'll use the same curly braces as we did in working with dictionary type of data. Let's say 3, 5 and 6 are elements of our set and now let's call our variable mySet and that's variable as we can now see is populated with elements 3, 5 and 6. And as you can see dictionary data and set data are stored in the same braces and if we want to work with them and to populate them we'll use the same curly braces and that is one of the reasons because if we have an empty dictionary we'll get result with empty curly braces and if we have an empty set we cannot use that same empty curly braces to define that our set is empty so in Python programming language they decided to use set with empty parentheses as value that represents that set is empty. And finally we have the fourth data structure in Python programming language which is tuple. Let's make an empty tuple by calling builtin function tuple. If we call our myTuple variable we'll see that our tuple is empty and values of tuple are stored inside parentheses so if we want to populate our tuple we'll use parentheses and we'll put inside it some values for example numbers 1, 3 and 5 and if we call myTuple we'll get as result our tuple populated with those numbers so that's it for this lesson. In this lesson we talked about four built-in data structures in Python Thanks for watching. Happy coding!