Python Variables

Python Variables

Introduction
Variables are used in Python to store data values. They act as placeholders to hold different types of data, such as numbers, strings, or objects. Python is a dynamically typed language, which means you don't need to declare the data type of a variable explicitly. Instead, Python infers the data type based on the value assigned to the variable.

Variable Naming Rules

• Variable names must start with a letter (a-z, A-Z) or an underscore (_).
• The rest of the variable name can consist of letters, digits (0-9), and underscores.
• Variable names are case-sensitive. For example, myVariable and myvariable are considered different variables.

Example: Declaring Variables

python
# Integer variable
age = 25

# String variable
name = "John Doe"

# Floating-point variable
salary = 3500.50

# Boolean variable
is_student = True

Explanation
In this example, we declared four different variables:

• age to store the integer value 25.
• name to store the string value "John Doe".
• salary to store the floating-point value 3500.50.
• is_student to store the boolean value True.

Dynamic Typing
Python allows you to change the data type of a variable on-the-fly.

python
x = 10
print(x)  # Output: 10

x = "Hello"
print(x)  # Output: Hello

Variable Reassignment
You can reassign values to a variable at any point in the code.

python
count = 5
print(count)  # Output: 5

count = count + 1
print(count)  # Output: 6

Conclusion
In Python, variables serve as containers for storing data values. They are fundamental to perform various operations and calculations in Python programs. Remember to choose meaningful names for your variables to enhance code readability.