Calculator using Tkinter 🧮

📌 About

A simple and functional Desktop Calculator built using Python's built-in Tkinter library. This project performs basic arithmetic operations through an interactive GUI (Graphical User Interface) window — no browser or web server needed!

---

⚙️ Features

• Addition ➕
• Subtraction ➖
• Multiplication ✖️
• Division ➗
• Backspace button (<-) — delete last entered digit
• Clear Everything button (CE) — reset the display

---

🛠️ Libraries Used

Library	Purpose
tkinter	Built-in Python library for creating the GUI window, buttons & entry box

No external libraries needed — tkinter comes pre-installed with Python! ✅

---

📂 Project Structure

Calculator-Using-Tkinter/
│
├── CALCULATOR USING TKINTER.py       ← Main Python script
├── README.md                            ← Project documentation
└── calculator_screenshot.png

---

▶️ How to Run

Step 1 — Make sure Python is installed:

python --version

Step 2 — Run the script:

python calculator.py

Step 3 — Calculator window opens automatically! ✅

---

🔍 How It Works

Step 1 → User enters first number using number buttons (0-9)
Step 2 → User clicks an operator button (+, -, x, %)
         → First number is stored
         → Display is cleared for second number
Step 3 → User enters second number
Step 4 → User clicks = button
         → Calculation is performed
         → Result is displayed

---

🧠 Key Functions Explained

Function	What it does
click(num)	Appends clicked number to the display
add()	Stores first number & sets operation to addition
sub()	Stores first number & sets operation to subtraction
mult()	Stores first number & sets operation to multiplication
div()	Stores first number & sets operation to division
equal()	Reads second number, performs operation & shows result
back()	Deletes last digit from display
clear()	Clears entire display

---

💡 Concepts Used

• tkinter — GUI window creation
• Entry widget — display box for numbers
• Button widget — number & operator buttons
• global variables — storing first number & operation type
• lambda functions — passing arguments to button commands
• if / elif logic — selecting correct math operation

---

🔗 References

• Python Tkinter Documentation
• Python Official Website