diff --git a/Day1_calculator.py b/Day1_calculator.py
new file mode 100644
index 000000000..e73493ec7
--- /dev/null
+++ b/Day1_calculator.py
@@ -0,0 +1,13 @@
+#Calculator
+num1=int(input())
+num2=int(input())
+sum=num1+num2
+print(f"Sum of {num1} and {num2} is {sum}")
+diff=num1-num2
+print(f"Difference of {num1} and {num2} is {diff}")
+mul=num1*num2
+print(f"Multiplication of {num1} and {num2} is {mul}")
+div=num1/num2
+print(f"Division of {num1} and {num2} is {div}")
+mod=num1%num2
+print(f"Modulus of {num1} and {num2} is {mod}")
\ No newline at end of file
diff --git a/NDV_code_by_Vasanthi_StudentRecord/Day1_calculator.py b/NDV_code_by_Vasanthi_StudentRecord/Day1_calculator.py
new file mode 100644
index 000000000..e73493ec7
--- /dev/null
+++ b/NDV_code_by_Vasanthi_StudentRecord/Day1_calculator.py
@@ -0,0 +1,13 @@
+#Calculator
+num1=int(input())
+num2=int(input())
+sum=num1+num2
+print(f"Sum of {num1} and {num2} is {sum}")
+diff=num1-num2
+print(f"Difference of {num1} and {num2} is {diff}")
+mul=num1*num2
+print(f"Multiplication of {num1} and {num2} is {mul}")
+div=num1/num2
+print(f"Division of {num1} and {num2} is {div}")
+mod=num1%num2
+print(f"Modulus of {num1} and {num2} is {mod}")
\ No newline at end of file
diff --git a/NDV_code_by_Vasanthi_StudentRecord/README.md b/NDV_code_by_Vasanthi_StudentRecord/README.md
new file mode 100644
index 000000000..d458dd0ff
--- /dev/null
+++ b/NDV_code_by_Vasanthi_StudentRecord/README.md
@@ -0,0 +1 @@
+This folder contains student record files.
diff --git a/NDV_code_by_Vasanthi_StudentRecord/StudentRecordManagement.py b/NDV_code_by_Vasanthi_StudentRecord/StudentRecordManagement.py
new file mode 100644
index 000000000..a97879f42
--- /dev/null
+++ b/NDV_code_by_Vasanthi_StudentRecord/StudentRecordManagement.py
@@ -0,0 +1,112 @@
+import json
+import os
+
+DATA_FILE = "students.json"
+
+class Student:
+    def __init__(self, student_id, name, branch, year, marks):
+        self.student_id = student_id
+        self.name = name
+        self.branch = branch
+        self.year = year
+        self.marks = marks
+
+    def to_dict(self):
+        return {
+            "Student ID": self.student_id,
+            "Name": self.name,
+            "Branch": self.branch,
+            "Year": self.year,
+            "Marks": self.marks
+        }
+
+class StudentManager:
+    def __init__(self):
+        self.students = []
+        self.load_data()
+
+    def load_data(self):
+        if os.path.exists(DATA_FILE):
+            with open(DATA_FILE, "r") as file:
+                data = json.load(file)
+                for item in data:
+                    self.students.append(Student(**item))
+
+    def save_data(self):
+        with open(DATA_FILE, "w") as file:
+            json.dump([s.to_dict() for s in self.students], file, indent=4)
+
+    def add_student(self):
+        student_id = input("Enter Student ID: ")
+        name = input("Enter Name: ")
+        branch = input("Enter Branch: ")
+        year = input("Enter Year: ")
+        marks = float(input("Enter Marks: "))
+        student = Student(student_id, name, branch, year, marks)
+        self.students.append(student)
+        self.save_data()
+        print("✅ Student added successfully.")
+
+    def view_students(self):
+        if not self.students:
+            print("No student records found.")
+            return
+
+        print("\n{:<12} {:<15} {:<10} {:<6} {:<6}".format("Student ID", "Name", "Branch", "Year", "Marks"))
+        print("-" * 55)
+        for s in self.students:
+            print("{:<12} {:<15} {:<10} {:<6} {:<6}".format(
+                s.student_id, s.name, s.branch, s.year, s.marks))
+
+    def update_student(self):
+        student_id = input("Enter Student ID to update: ")
+        for s in self.students:
+            if s.student_id == student_id:
+                s.name = input("Enter new Name: ")
+                s.branch = input("Enter new Branch: ")
+                s.year = input("Enter new Year: ")
+                s.marks = float(input("Enter new Marks: "))
+                self.save_data()
+                print("✅ Student record updated.")
+                return
+        print("❌ Student not found.")
+
+    def delete_student(self):
+        student_id = input("Enter Student ID to delete: ")
+        for s in self.students:
+            if s.student_id == student_id:
+                self.students.remove(s)
+                self.save_data()
+                print("✅ Student record deleted.")
+                return
+        print("❌ Student not found.")
+
+def main():
+    manager = StudentManager()
+
+    while True:
+        print("\n=== Student Record Management ===")
+        print("1. Add Student")
+        print("2. View All Students")
+        print("3. Update Student")
+        print("4. Delete Student")
+        print("5. Exit")
+
+        choice = input("Enter your choice: ")
+
+        if choice == "1":
+            manager.add_student()
+        elif choice == "2":
+            manager.view_students()
+        elif choice == "3":
+            manager.update_student()
+        elif choice == "4":
+            manager.delete_student()
+        elif choice == "5":
+            print("Exiting... 👋")
+            break
+        else:
+            print("❌ Invalid choice. Try again.")
+
+if __name__ == "__main__":
+    main()
diff --git a/NDV_code_by_Vasanthi_StudentRecord/students.json b/NDV_code_by_Vasanthi_StudentRecord/students.json
new file mode 100644
index 000000000..39e59f813
--- /dev/null
+++ b/NDV_code_by_Vasanthi_StudentRecord/students.json
@@ -0,0 +1,9 @@
+[
+    {
+        "Student ID": "130",
+        "Name": "Yash",
+        "Branch": "AI & ML",
+        "Year": "2020",
+        "Marks": 986.0
+    }
+]
\ No newline at end of file
diff --git a/NDV_code_by_Vasanthi_StudentRecord/tax_calculator.py b/NDV_code_by_Vasanthi_StudentRecord/tax_calculator.py
new file mode 100644
index 000000000..c632f1712
--- /dev/null
+++ b/NDV_code_by_Vasanthi_StudentRecord/tax_calculator.py
@@ -0,0 +1,82 @@
+def calculate_old_regime_tax(gross_income, hra_claimed, sec_80c=150000, std_deduction=50000):
+    # Total deductions allowed under old regime
+    total_deductions = std_deduction + sec_80c + hra_claimed
+    taxable_income = gross_income - total_deductions
+    tax = 0
+
+    # Old regime tax slabs
+    if taxable_income <= 250000:
+        tax = 0
+    elif taxable_income <= 500000:
+        tax = (taxable_income - 250000) * 0.05
+    elif taxable_income <= 1000000:
+        tax = (250000 * 0.05) + (taxable_income - 500000) * 0.20
+    else:
+        tax = (250000 * 0.05) + (500000 * 0.20) + (taxable_income - 1000000) * 0.30
+
+    # Rebate under section 87A
+    if taxable_income <= 500000:
+        tax = 0
+
+    return max(0, tax), max(0, taxable_income)
+
+
+def calculate_new_regime_tax(income):
+    tax = 0
+
+    # New regime tax slabs
+    if income <= 300000:
+        tax = 0
+    elif income <= 600000:
+        tax = (income - 300000) * 0.05
+    elif income <= 900000:
+        tax = (300000 * 0.05) + (income - 600000) * 0.10
+    elif income <= 1200000:
+        tax = (300000 * 0.05) + (300000 * 0.10) + (income - 900000) * 0.15
+    elif income <= 1500000:
+        tax = (300000 * 0.05) + (300000 * 0.10) + (300000 * 0.15) + (income - 1200000) * 0.20
+    else:
+        tax = (300000 * 0.05) + (300000 * 0.10) + (300000 * 0.15) + (300000 * 0.20) + (income - 1500000) * 0.30
+
+    # Rebate under section 87A
+    if income <= 700000:
+        tax = 0
+
+    return max(0, tax)
+
+
+def main():
+    print("=== Income Tax Calculator: Old vs New Regime ===")
+
+    try:
+        ctc = float(input("Enter your Annual CTC (₹): "))
+        bonus = float(input("Enter your Annual Bonus (₹): "))
+        hra = float(input("Enter your HRA claimed under Old Regime (₹): "))
+    except ValueError:
+        print("❌ Invalid input. Please enter numbers only.")
+        return
+
+    # Step 1: Calculate gross income
+    gross_income = ctc + bonus
+    print(f"\nTotal Income including Bonus = ₹{gross_income:,.2f}")
+
+    # Step 2: Calculate taxes under both regimes
+    old_tax, old_taxable_income = calculate_old_regime_tax(gross_income, hra)
+    new_tax = calculate_new_regime_tax(gross_income)
+
+    # Step 3: Display comparison
+    print("\n--- Tax Calculation Summary ---")
+    print(f"Taxable Income under Old Regime: ₹{old_taxable_income:,.2f}")
+    print(f"Tax under Old Regime: ₹{old_tax:,.2f}")
+    print(f"Tax under New Regime: ₹{new_tax:,.2f}")
+
+    print("\n--- Comparison Summary ---")
+    if old_tax < new_tax:
+        print("✅ Old Regime is better. You save more tax.")
+    elif new_tax < old_tax:
+        print("✅ New Regime is better. You save more tax.")
+    else:
+        print("⚖️ Both regimes result in the same tax.")
+
+if __name__ == "__main__":
+    main()
diff --git a/StudentRecordManagement.py b/StudentRecordManagement.py
new file mode 100644
index 000000000..a97879f42
--- /dev/null
+++ b/StudentRecordManagement.py
@@ -0,0 +1,112 @@
+import json
+import os
+
+DATA_FILE = "students.json"
+
+class Student:
+    def __init__(self, student_id, name, branch, year, marks):
+        self.student_id = student_id
+        self.name = name
+        self.branch = branch
+        self.year = year
+        self.marks = marks
+
+    def to_dict(self):
+        return {
+            "Student ID": self.student_id,
+            "Name": self.name,
+            "Branch": self.branch,
+            "Year": self.year,
+            "Marks": self.marks
+        }
+
+class StudentManager:
+    def __init__(self):
+        self.students = []
+        self.load_data()
+
+    def load_data(self):
+        if os.path.exists(DATA_FILE):
+            with open(DATA_FILE, "r") as file:
+                data = json.load(file)
+                for item in data:
+                    self.students.append(Student(**item))
+
+    def save_data(self):
+        with open(DATA_FILE, "w") as file:
+            json.dump([s.to_dict() for s in self.students], file, indent=4)
+
+    def add_student(self):
+        student_id = input("Enter Student ID: ")
+        name = input("Enter Name: ")
+        branch = input("Enter Branch: ")
+        year = input("Enter Year: ")
+        marks = float(input("Enter Marks: "))
+        student = Student(student_id, name, branch, year, marks)
+        self.students.append(student)
+        self.save_data()
+        print("✅ Student added successfully.")
+
+    def view_students(self):
+        if not self.students:
+            print("No student records found.")
+            return
+
+        print("\n{:<12} {:<15} {:<10} {:<6} {:<6}".format("Student ID", "Name", "Branch", "Year", "Marks"))
+        print("-" * 55)
+        for s in self.students:
+            print("{:<12} {:<15} {:<10} {:<6} {:<6}".format(
+                s.student_id, s.name, s.branch, s.year, s.marks))
+
+    def update_student(self):
+        student_id = input("Enter Student ID to update: ")
+        for s in self.students:
+            if s.student_id == student_id:
+                s.name = input("Enter new Name: ")
+                s.branch = input("Enter new Branch: ")
+                s.year = input("Enter new Year: ")
+                s.marks = float(input("Enter new Marks: "))
+                self.save_data()
+                print("✅ Student record updated.")
+                return
+        print("❌ Student not found.")
+
+    def delete_student(self):
+        student_id = input("Enter Student ID to delete: ")
+        for s in self.students:
+            if s.student_id == student_id:
+                self.students.remove(s)
+                self.save_data()
+                print("✅ Student record deleted.")
+                return
+        print("❌ Student not found.")
+
+def main():
+    manager = StudentManager()
+
+    while True:
+        print("\n=== Student Record Management ===")
+        print("1. Add Student")
+        print("2. View All Students")
+        print("3. Update Student")
+        print("4. Delete Student")
+        print("5. Exit")
+
+        choice = input("Enter your choice: ")
+
+        if choice == "1":
+            manager.add_student()
+        elif choice == "2":
+            manager.view_students()
+        elif choice == "3":
+            manager.update_student()
+        elif choice == "4":
+            manager.delete_student()
+        elif choice == "5":
+            print("Exiting... 👋")
+            break
+        else:
+            print("❌ Invalid choice. Try again.")
+
+if __name__ == "__main__":
+    main()
diff --git a/students.json b/students.json
new file mode 100644
index 000000000..39e59f813
--- /dev/null
+++ b/students.json
@@ -0,0 +1,9 @@
+[
+    {
+        "Student ID": "130",
+        "Name": "Yash",
+        "Branch": "AI & ML",
+        "Year": "2020",
+        "Marks": 986.0
+    }
+]
\ No newline at end of file
diff --git a/tax_calculator.py b/tax_calculator.py
new file mode 100644
index 000000000..c632f1712
--- /dev/null
+++ b/tax_calculator.py
@@ -0,0 +1,82 @@
+def calculate_old_regime_tax(gross_income, hra_claimed, sec_80c=150000, std_deduction=50000):
+    # Total deductions allowed under old regime
+    total_deductions = std_deduction + sec_80c + hra_claimed
+    taxable_income = gross_income - total_deductions
+    tax = 0
+
+    # Old regime tax slabs
+    if taxable_income <= 250000:
+        tax = 0
+    elif taxable_income <= 500000:
+        tax = (taxable_income - 250000) * 0.05
+    elif taxable_income <= 1000000:
+        tax = (250000 * 0.05) + (taxable_income - 500000) * 0.20
+    else:
+        tax = (250000 * 0.05) + (500000 * 0.20) + (taxable_income - 1000000) * 0.30
+
+    # Rebate under section 87A
+    if taxable_income <= 500000:
+        tax = 0
+
+    return max(0, tax), max(0, taxable_income)
+
+
+def calculate_new_regime_tax(income):
+    tax = 0
+
+    # New regime tax slabs
+    if income <= 300000:
+        tax = 0
+    elif income <= 600000:
+        tax = (income - 300000) * 0.05
+    elif income <= 900000:
+        tax = (300000 * 0.05) + (income - 600000) * 0.10
+    elif income <= 1200000:
+        tax = (300000 * 0.05) + (300000 * 0.10) + (income - 900000) * 0.15
+    elif income <= 1500000:
+        tax = (300000 * 0.05) + (300000 * 0.10) + (300000 * 0.15) + (income - 1200000) * 0.20
+    else:
+        tax = (300000 * 0.05) + (300000 * 0.10) + (300000 * 0.15) + (300000 * 0.20) + (income - 1500000) * 0.30
+
+    # Rebate under section 87A
+    if income <= 700000:
+        tax = 0
+
+    return max(0, tax)
+
+
+def main():
+    print("=== Income Tax Calculator: Old vs New Regime ===")
+
+    try:
+        ctc = float(input("Enter your Annual CTC (₹): "))
+        bonus = float(input("Enter your Annual Bonus (₹): "))
+        hra = float(input("Enter your HRA claimed under Old Regime (₹): "))
+    except ValueError:
+        print("❌ Invalid input. Please enter numbers only.")
+        return
+
+    # Step 1: Calculate gross income
+    gross_income = ctc + bonus
+    print(f"\nTotal Income including Bonus = ₹{gross_income:,.2f}")
+
+    # Step 2: Calculate taxes under both regimes
+    old_tax, old_taxable_income = calculate_old_regime_tax(gross_income, hra)
+    new_tax = calculate_new_regime_tax(gross_income)
+
+    # Step 3: Display comparison
+    print("\n--- Tax Calculation Summary ---")
+    print(f"Taxable Income under Old Regime: ₹{old_taxable_income:,.2f}")
+    print(f"Tax under Old Regime: ₹{old_tax:,.2f}")
+    print(f"Tax under New Regime: ₹{new_tax:,.2f}")
+
+    print("\n--- Comparison Summary ---")
+    if old_tax < new_tax:
+        print("✅ Old Regime is better. You save more tax.")
+    elif new_tax < old_tax:
+        print("✅ New Regime is better. You save more tax.")
+    else:
+        print("⚖️ Both regimes result in the same tax.")
+
+if __name__ == "__main__":
+    main()