Variables and Data Types in Python

Python is a dynamically typed language, meaning you don’t need to declare the type of a variable when defining it. Python automatically assigns the data type based on the value. This article explains variables and the most common data types in Python: int, float, string, and boolean.

1. Variables in Python

Variables in Python are used to store data values. A variable is created as soon as a value is assigned to it.

          
            # Example 1: Variable assignment
            x = 10  # Integer
            name = "Alice"  # String
            pi = 3.14  # Float

            print(x)
            print(name)
            print(pi)
          
        

Output:

          10
          Alice
          3.14
        

2. Data Types

Python provides several built-in data types. Let’s discuss the most common ones.

2.1 Integer (int)

The int data type is used to represent whole numbers.

          
            # Example 2: Working with integers
            a = 5
            b = 10
            sum = a + b
            print("Sum of integers:", sum)
          
        

Output:

          Sum of integers: 15
        

2.2 Float (float)

The float data type is used to represent decimal or floating-point numbers.

          
            # Example 3: Working with floats
            c = 2.5
            d = 4.8
            result = c * d
            print("Product of floats:", result)
          
        

Output:

          Product of floats: 12.0
        

2.3 String (str)

The string data type is used to represent text. Strings are enclosed in single, double, or triple quotes.

          
            # Example 4: Working with strings
            greeting = "Hello"
            name = "Bob"
            message = greeting + ", " + name + "!"
            print(message)
          
        

Output:

          Hello, Bob!
        

2.4 Boolean (bool)

The boolean data type represents two values: True or False.

          
            # Example 5: Working with booleans
            is_python_fun = True
            is_java_fun = False

            print("Is Python fun?", is_python_fun)
            print("Is Java fun?", is_java_fun)
          
        

Output:

          Is Python fun? True
          Is Java fun? False
        

3. Type Checking

In Python, you can check the type of a variable using the type() function.

          
            # Example 6: Checking variable types
            print(type(10))          # int
            print(type(3.14))        # float
            print(type("Python"))    # str
            print(type(True))        # bool
          
        

Output:

4. Dynamic Typing

Python allows variables to change their data type during runtime because it is dynamically typed.

          
            # Example 7: Dynamic typing
            var = 10  # int
            print("Before:", var, type(var))

            var = "Now I'm a string"  # str
            print("After:", var, type(var))
          
        

Output:

          Before: 10 
          After: Now I'm a string 
        

Conclusion

Python's support for multiple data types and its dynamic nature make it a powerful and flexible language. Understanding variables and data types is essential for writing efficient Python programs.