Variables and Data Types in Python

 In Python, a variable is a named location in memory that is used to store a value. Variables are used to store data that can be accessed and modified throughout the program.

To create a variable in Python, you simply assign a value to a name using the assignment operator (=). For example:

x = 5
y = "Hello"
z = [1, 2, 3]

In the above example, x is assigned the value 5, y is assigned the value "Hello" and z is assigned the value [1, 2, 3].

Python has several built-in data types, including:

• int: used to represent integers (whole numbers)
• float: used to represent real numbers (numbers with decimal points)
• str: used to represent strings (text)
• list: used to represent a collection of items
• tuple: similar to a list, but immutable (cannot be modified)
• dict: used to represent a collection of key-value pairs
• set: used to represent a collection of unique items

You can use the type() function to check the data type of a variable:

x = 5
print(type(x))  # Output: <class 'int'>

y = "Hello"
print(type(y))  # Output: <class 'str'>

z = [1, 2, 3]
print(type(z))  # Output: <class 'list'>

It's important to know the data type of a variable as it can affect the way the variable can be used and processed in the program. For example, mathematical operations such as addition and multiplication work differently for different data types.

It's also possible to change the data type of a variable using type casting. For example:

x = 5
y = str(x)  # y is now a string with the value "5"

Python is a dynamically typed language which means that you don't have to specify the data type of a variable when you declare it, and the type of a variable can change during the execution of the program.