DEV Community: Punitha

Operator Overloading

Punitha — Tue, 30 Jun 2026 01:54:56 +0000

What is Operator Overloading?

Operator overloading allows operators such as +, -, *, and == to have different meanings depending on the objects they are used with.

Example 1:

a = "Hello"
b = "Python"

print(a + b)

Output:

Hello Python    -> + operator joins two strings instead of performing addition.

Example 2:

print(5 + 3)

Output:

8               -> + operator performs arithmetic addition.

Symbols and Operators

Punitha — Tue, 30 Jun 2026 01:54:21 +0000

What are Symbols and Operators?

Symbols are special characters used in Python to represent operations or actions.
Operators are symbols that perform specific operations on variables and values.

Example:

a = 10          ->  a and b are operands
b = 5           ->  = is an assignment operator

c = a + b       ->  + is an arithmetic operator

Symbol and Operator Name

Arithmetic Operators 
  +                                     Addition
  -                                     Subtraction
  *                                     Multiplication
  /                                     Division/True division
  //                                    Floor division
  %                                     Modulus
  **                                    Power/Exponent

Comparison Operators
  ==                                    Equal to
  !=                                    Not Equal
  >                                     Greater than
  >=                                    Greater than or equal to
  <                                     Less than
  <=                                    Less than or equal to

Logical Operators
  and                                   Logical AND
  or                                    Logical OR
  Not                                   Logical NOT

Identity Operators:

Used to check whether two variables refer to the same object.

Identity Operators
  is                                    Identity      
  is not                                Not Identity

Membership Operators:

Used to check whether a value exists in a sequence.

Membership Operators
  in                                    Membership
  not in                                Not Membership

Variables/Identifiers

Punitha — Tue, 30 Jun 2026 01:53:23 +0000

What is a Variables?

A Variables is a container used to store data values in program.
Example:

name = "Python"
age = 21

Variable Naming Conventions:

Can contain letters, numbers, and underscore(_)
Must start with a letter or underscore
Cannot start with a number
Cannot contain spaces
Cannot use Python keywords
special characters are not allowed

Multi-words Variable Names:

Camel Case - Each word except the first, start with a capital letter.

Example:

studentName
employeeSalary

Pascal Case - Each word start with a capital letter.

Example:

StudentName
EmployeeSalary

Snake Case - each word is separated by an underscore character.

Example:

student_name
employee_salary

Data Types

Punitha — Mon, 29 Jun 2026 13:51:59 +0000

Why Programming?
Programming is the process of writing instructions that tell a computer what to do.
What is a Data Types?
A data type Specific the type of value that a variable can store.
What is a Primitive Data Types?
Primitive data types are the basic built-in data types that store a single value.
int -> Integer numbers -> (10, -5)
float -> Decimal numbers -> (3.14, 25.5)
str -> Text/String -> ("Hello")
bool -> Boolean values -> (True, False)

Example:

age = 21         -> integer
price = 99.99    -> float
name = "Python"  -> string
is_pass = True   -> boolean

What is a Built-in Function in Python?

A built-in function is a function that is already available in Python.

print()
input()
len()
type()

print() -> Display output on the screen

print("Hello World")

Output

Hello World

input() -> Takes input form the user

name = input("Enter your name: ")

Output

Enter your name:

len() -> Returns the length of a string, list, etc.

name = "Python"
print(len(name))

Output

type() -> Returns the data type of a variable

x = 10
print(type(x))

Output

<class 'int'>

Introduction to Python

Punitha — Mon, 29 Jun 2026 13:30:42 +0000

What is Python?
- Python is a high-level, easy-to-learn programming language.
- Python is an interpreted, object-oriented, and general-purpose programming language.
Where is Python used?
- Web Development
- Data Analysis
- Artificial Intelligence
- Machine Learning
- Automation
Difference between Compiler and Interpreter?
Compiler:
* Translates the entire program at once
* One language to another language
* Whole execute
* Shows all errors after compilation
* Example: C, C++
Interpreter:
* Translates one line at a time
* One language to another language
* Execute line by line
* Shows errors one by one while executing
* Example: Python, JavaScript
Who created Python?
Guido van Rossum created Python and was first released in 1991.
Run:
- Py hello.py
- Python hello.py
- Python3 hello.py
- File to run --> Scripting mode
- Terminal run --> Interactive mode