diff --git a/easyPythonpi/easyPythonpi.py b/easyPythonpi/easyPythonpi.py
index a963b89..147095d 100644
--- a/easyPythonpi/easyPythonpi.py
+++ b/easyPythonpi/easyPythonpi.py
@@ -1,24 +1,72 @@
-
-"""  A python module that helps you to calculate some of the  most used calculations.....
+""" A Python module that helps you to calculate some of the most used calculations.....
     usage--
-            Just download the file from git and unzip in ur system.
+            Just download the file from git and unzip it on your system.
             And while using this module, just write as code-
-            'from easypythonpi import *' and u r good to go...
-                            ~Happy programming"""
-                        
-
-# Programmer defined exceptions go here:
-
-# define exception for invalid Binary Strings  
+            'from easypythonpi import *' and you're good to go...
+                            ~Happy programming
+"""
 
+# Programmer-defined exceptions
 class InvalidBinaryException(Exception):
+    """Raised when an invalid binary string is provided."""
     pass
 
 class InvalidNumberFibException(Exception):
+    """Raised when the Fibonacci number is invalid."""
     def __init__(self, n, message="n is not valid, must be greater than or equal to 1"):
-         self.n = n
-         self.message = message
-         
+        self.n = n
+        self.message = message
+        super().__init__(self.message)
+
 class InvalidMeasurementShapeException(Exception):
-    def __init__(self, message="invalid measurement, must be greater than or equal to 0"):
-        self.message = message
\ No newline at end of file
+    """Raised when invalid measurement values are provided for shapes."""
+    def __init__(self, message="Invalid measurement, must be greater than or equal to 0"):
+        self.message = message
+        super().__init__(self.message)
+
+# Function definitions
+def add(x, y):
+    """Return the sum of x and y."""
+    return x + y
+
+def subtract(x, y):
+    """Return the difference of x and y."""
+    return x - y
+
+def multiply(x, y):
+    """Return the product of x and y."""
+    return x * y
+
+def divide(x, y):
+    """Return the quotient of x and y, or an error message if dividing by zero."""
+    if y == 0:
+        return "Cannot divide by zero"
+    return x / y
+
+if __name__ == "__main__":
+    # Simple calculator usage
+    print("Please select operation -\n"
+          "1. Add\n"
+          "2. Subtract\n"
+          "3. Multiply\n"
+          "4. Divide\n")
+
+    try:
+        select = int(input("Select operations from 1, 2, 3, 4: "))
+        number_1 = float(input("Enter first number: "))
+        number_2 = float(input("Enter second number: "))
+
+        if select == 1:
+            print(f"{number_1} + {number_2} = {add(number_1, number_2)}")
+        elif select == 2:
+            print(f"{number_1} - {number_2} = {subtract(number_1, number_2)}")
+        elif select == 3:
+            print(f"{number_1} * {number_2} = {multiply(number_1, number_2)}")
+        elif select == 4:
+            result = divide(number_1, number_2)
+            print(f"{number_1} / {number_2} = {result}")
+        else:
+            print("Invalid input, please select a number between 1 and 4.")
+   
+    except ValueError:
+        print("Error: Please enter valid numbers.")