diff --git a/team_2_library.py b/team_2_library.py
new file mode 100644
index 0000000..0d57919
--- /dev/null
+++ b/team_2_library.py
@@ -0,0 +1,296 @@
+import json
+import os
+
+class Book():
+                
+    def __init__(self, title, author, publication_year):
+        self.title = title
+        self.author = author
+        self.publication_year = publication_year
+        self.is_borrowed = False            #False=kitap kutuphanede. True=kitap alinmis. False ile baslar
+        self.borrowed_by = None             #basta kimse kitap almadigi icin None ile baslatilir. Biri aldiysa ismi yazilir
+    
+    def show_info(self):
+        status = "Borrowed" if self.is_borrowed else "Available"   
+        print("Book Info")
+        print("Title :", self.title)
+        print("Author:", self.author)
+        print("Year  :", self.publication_year)
+        print("Status:", status)
+
+
+    def borrow(self, user):
+        if not self.is_borrowed:                               #kitap kimse tarafindan alinmamissa, musaitse
+            self.is_borrowed = True                            
+            self.borrowed_by = user.name                       
+            user.borrowed_books.append(self.title)             #basligi ekliyor
+            print(f"{user.name} borrowed '{self.title}'.")
+        else:                                                  #musait degilse kimin aldigini soyler   
+            print(f"'{self.title}' is already borrowed by {self.borrowed_by}.")
+
+    def return_book(self,user):
+        if self.is_borrowed and self.borrowed_by == user.name:          #kitap biri tarafinda alinmissa
+            self.is_borrowed = False                                    #kitap kutuphaneye geri dondu
+            self.borrowed_by = None                                     #artik bir kullanicida degil
+            user.borrowed_books.remove(self.title)
+            print(f"'{user.name}' has successfully returned '{self.title}'.")
+        
+        elif not self.is_borrowed:
+            print(f"'{self.title}' is already in the library.")
+        
+        else:
+            print(f"'{self.title}' was borrowed by another user.")
+
+
+    def to_dict(self):         # Kitap bilgisini JSON'a uygun hale getirir. 
+        return {
+            "title": self.title,
+            "author": self.author,
+            "publication_year": self.publication_year,
+            "is_borrowed": self.is_borrowed,
+            "borrowed_by": self.borrowed_by
+            }
+        
+
+#-----------------------------------------------
+
+class Novel(Book):
+    def __init__(self, title, author, publication_year, genre):
+        super().__init__(title, author, publication_year)           #book sinifinin __init__ methodunu cagirir
+        self.genre = genre                  #genre= tur demek
+        
+    def to_dict(self):
+        data = super().to_dict()            #book daki to_dict cagirilir
+        data["genre"] = self.genre 
+        return data
+    
+    
+class Magazine(Book):
+    def __init__(self, title, author, publication_year, issue):
+        super().__init__(title, author, publication_year)
+        self.issue = issue
+        
+    def to_dict(self):
+        data = super().to_dict()
+        data["issue"] = self.issue
+        return data
+    
+#--------------------------------
+
+
+class User():
+    def __init__(self, name, password):
+        self.name = name
+        self.password = password
+        self.borrowed_books = []
+        
+    def borrow_book(self,book):
+        book.borrow(self)
+
+    def return_book(self,book):
+        book.return_book(self)
+
+    def list_borrowed_books(self):
+        print(f"Borrowed books of user '{self.name}': ")
+        if not self.borrowed_books:
+            print(" No borrowed books.")
+        else:
+            for title in self.borrowed_books:
+                print(f"   - {title}")
+
+    def to_dict(self):
+        return {
+            "name": self.name,
+            "password": self.password,
+            "borrowed_books": self.borrowed_books
+        }
+
+#--------------------------
+
+class Library():
+        def __init__(self, name):
+           self.name = name
+           self.books = []
+           self.users = []
+
+        def add_book(self,book):
+           self.books.append(book)
+           print(f"Book '{book.title}' added to the library.")
+
+        
+        def add_user(self, user):
+            self.users.append(user)
+            print(f"User '{user.name}' added to the library '{self.name}'.")
+
+
+        def show_all_books(self):
+            print(f"{self.name} - All Books: ")
+            if not self.books:
+                print("No books in de library yet.")
+
+            else:
+                for book in self.books:
+                    book.show_info()
+
+        def login(self, name, password):
+            for user in self.users:
+                if user.name == name and user.password == password:
+                    print(f"Welcome, {name}!")
+                    return user
+            print("Invalid username or password.")
+            return None            
+           
+#----------------------------
+#json a kaydetme ve yukleme
+
+        def save(self, filename="library_data.json"):
+            data = {
+                "name": self.name,                                          #kutuphanenin adi
+                "books": [book.to_dict() for book in self.books],           #self.books içindeki her book nesnesi için book.to_dict() çağrılır.
+                "users": [user.to_dict() for user in self.users]
+            }
+            with open(filename, "w", encoding="utf-8") as f:
+                json.dump(data, f, indent=4)
+            print(f"Library data saved to '{filename}'.")
+
+
+
+        def load(self, filename="library_data.json"):           #kaydedilmis veriyi geri yukler (self nesnesine) yeniden kullanima sokar
+            if not os.path.exists(filename):
+                print("No saved data found.")
+                return
+            with open(filename, "r", encoding="utf-8") as f:
+             data = json.load(f)                                #json.load(f) ile JSON formatındaki veri Python sözlüğüne (dict) çevrilir.
+
+            self.name = data["name"]                            #kutuphanenin adi self.name olarak ayarlanir
+            
+            #Kitapları (books) Yeniden Oluşturma
+            self.books = []                                     
+            for b in data["books"]:                             
+                if "genre" in b:
+                    book = Novel(b["title"], b["author"], b["publication_year"], b["genre"])
+                elif "issue" in b:
+                    book = Magazine(b["title"], b["author"], b["publication_year"], b["issue"])
+                else:
+                    book = Book(b["title"], b["author"], b["publication_year"])
+                book.is_borrowed = b["is_borrowed"]             #kitap oduncte mi
+                book.borrowed_by = b["borrowed_by"]             #kim odunc aldi
+                self.books.append(book)
+
+            self.users = []
+            for u in data["users"]:
+                user = User(u["name"], u["password"])
+                user.borrowed_books = u["borrowed_books"]
+                self.users.append(user)
+
+        def exit(self):
+            print('Thanks for using')
+            self.save()
+
+
+#ana menu  
+def main():
+    library = Library("My Library")
+    library.load()               # JSON varsa eski verileri yükle
+
+    print("---Welcome to the Library System---")
+
+    # Login veya yeni hesap oluşturma
+    user = None                              #henuz giris yapmis bir kullanici yok
+    while not user:                          #kullanıcı başarılı şekilde giriş yapana kadar döngü devam eder.
+        print("1 - Log in")
+        print("2 - Create new account")
+        print("3 - Add book")
+        choice = input("Choose an option: ")
+
+        if choice == "1":
+            name = input("Username: ")
+            password = input("Password: ")
+            user = library.login(name, password)
+        elif choice == "2":                         #yeni hesap olusturma
+            name = input("Choose a username: ")
+            password = input("Choose a password: ")
+            new_user = User(name, password)
+            library.add_user(new_user)
+            user = new_user
+        elif choice == "3":                         #yeni hesap olusturma
+            print("1 -Standart")
+            print("2 -Novel")
+            print("3 -Magazine")
+            genre = int(input("Choose the genre of the book: "))
+            if genre == 1:
+                title = input("Title: ")
+                author = input("Author: ")
+                publication_year = int(input("Publication_year: "))
+
+                book = Book(title, author, publication_year)
+                library.add_book(book)
+                print("Book is added.")
+                library.save()
+            elif genre == 2:
+                title = input("Title: ")
+                author = input("Author: ")
+                publication_year = int(input("Publication_year: "))
+                book_genre = 'Novel'
+                book = Novel(title, author, publication_year, book_genre)
+                library.add_book(book)
+                print("Book is added.")
+                library.save()
+            elif genre == 3: 
+                title = input("Title: ")
+                author = input("Author: ")
+                publication_year = int(input("Publication_year: "))
+                book_genre = 'Magazine'
+                book = Magazine(title, author, publication_year, book_genre)
+                library.add_book(book)
+                print("Book is added.")
+                library.save()
+        else:
+            print("Invalid choice. Try again.")
+
+
+    while True:
+        print(f"=== Library Menu ({user.name}) ===")
+        print("1 - List all books")
+        print("2 - Borrow a book")
+        print("3 - Return a book")
+        print("4 - Show my borrowed books")
+        print("5 - Save and exit")
+
+        choice = input("Select an option: ")
+
+        if choice == "1":
+            library.show_all_books()
+
+        elif choice == "2":
+            title = input("Enter the title of the book to borrow: ")
+            for book in library.books:
+                if book.title.lower() == title.lower():
+                    user.borrow_book(book)              #kitap kutuphanede bulursa kullaniciya eklenir
+                    break
+            else:
+                print("Book not found.")
+
+        elif choice == "3":
+            title = input("Enter the title of the book to return: ")
+            for book in library.books:
+                if book.title.lower() == title.lower():
+                    user.return_book(book)                  #kitap kullanici listesinden silinir
+                    break
+            else:
+                print("Book not found.")
+
+        elif choice == "4":
+            user.list_borrowed_books()
+
+        elif choice == "5":
+            library.exit()
+            break
+
+        else:
+            print("Invalid option. Try again.")
+
+
+if __name__ == "__main__":
+    
+    main()
diff --git a/team_2_questions.py b/team_2_questions.py
new file mode 100644
index 0000000..1cdaee5
--- /dev/null
+++ b/team_2_questions.py
@@ -0,0 +1,141 @@
+# Q1==================================================
+class Rectangle():
+    def __init__(self,width, height):
+        self.width = width
+        self.height = height
+        
+    def area(self):
+        return self.width * self.height
+    
+    def perimeter(self):
+        return 2 * (self.width + self.height)
+    
+rect = Rectangle(5, 7)
+print("Area:", rect.area())
+print("Perimeter:", rect.perimeter())
+
+# Q2==================================================
+class School():
+    def __init__(self, name, foundation_year):
+        self.name = name
+        self.foundation_year = foundation_year
+        self.students = []
+        self.teachers = {}
+        
+    def add_new_student(self, student_name, class_name): 
+        self.students.append({"name": student_name, "class": class_name})
+
+    def add_new_teacher(self, teacher_name, branch):
+        self.teachers[teacher_name] = branch
+        
+    def view_student_list(self):
+        for student in self.students:
+            print(f"{student['name']} - Class: {student['class']}")
+            
+    def view_teacher_list(self):
+        for teacher, branch in self.teachers.items():
+            print(f"{teacher} - Branch: {branch}")  
+            
+my_school = School("Nilufer High School", 2014)
+my_school.add_new_student("Helin", "10A")
+my_school.add_new_student("Aya", "11B")
+my_school.add_new_teacher("Ms. Hulya", "Math")
+my_school.add_new_teacher("Ms. Yasemin", "Physics")
+
+my_school.view_student_list()
+my_school.view_teacher_list()
+
+# Q3==================================================
+class Shape():
+    def __init__(self, width, height):
+        self.width = width
+        self.height = height
+        
+class Rectangle(Shape):
+    def calculate_area(self):
+        return self.width * self.height
+    
+        
+class Square(Shape):
+    def calculate_area(self):
+        return self.width * self.width
+        
+rectangle = Rectangle(4, 8)
+square = Square(6,6)
+        
+print("Rectange Area:", rectangle.calculate_area())
+print("Square Area:", square.calculate_area())
+        
+# Q4==================================================
+class Vehicle():
+    def __init__(self, make, model, year):
+        self.make = make
+        self.model = model
+        self.year = year
+        
+class OffRoadVehicle(Vehicle):
+    def __init__(self, make, model, year, four_wheel_drive):
+        super().__init__(make, model, year)
+        self.four_wheel_drive = four_wheel_drive
+        
+        
+    
+class SportsCar(Vehicle): 
+    def __init__(self, make, model, year, max_speed):
+        super().__init__(make, model, year)
+        self.max_speed = max_speed
+        
+suv = OffRoadVehicle("Toyota", "Land Cruiser", 2022, True)
+sportscar = SportsCar("Ferrari", "F8 Tributo", 2023, 340)
+
+print("Off-Road Vehicle:")
+print(f"Make: {suv.make}, Model: {suv.model}, Year: {suv.year}, 4x4: {suv.four_wheel_drive}")
+
+print("\nSports Car:")
+print(f"Make: {sportscar.make}, Model: {sportscar.model}, Year: {sportscar.year}, Max Speed: {sportscar.max_speed} km/h")       
+
+
+# Q5==================================================
+
+class Customer():
+    def __init__(self, name, surname, tc_identification, phone):
+        self.name = name
+        self.surname = surname
+        self.tc_identification = tc_identification
+        self.phone = phone
+
+    def display_information(self):
+        print(f"Name: {self.name} {self.surname}")
+        print(f"TC ID: {self.tc_identification}")
+        print(f"Phone: {self.phone}")
+    
+    
+class Account(Customer):
+    def __init__(self, customer, account_number, balance):
+        self.customer = customer
+        self.account_number = account_number
+        self.balance = balance
+        
+    def display_information(self):                   #bilgi gosterme metodu
+        print(f"Name; {self.customer.name} {self.customer.surname}")
+        print(f"TC ID: {self.customer.tc_identification}")
+        print(f"Phone: {self.customer.phone}")
+        
+    def deposit(self, amount):                      #para yatirma metodu(deposit)
+        self.balance += amount                      #şu anki bakiye üzerine yeni yatırılan parayı ekler.
+        print(f"{amount} TL deposited. New balance: {self.balance}. TL")
+        
+    def money_check(self, amount):               #para cekme metodu
+        if amount <= self.balance:       
+            self.balance -= amount               #cekilmek istenen para cikariliyor sonuc guncel para
+            print(f"{amount} TL withdrawn. Remaining balance: {self.balance} TL")
+        else:
+            print("Insufficient balance! Transaction cancelled.")
+            
+    def display_balance(self):                      #bakiye gosterme metodu
+        print(f"Current balance: {self.balance}")
+        
+customer1 = Customer("Yasemin", "Kalemli", "3452347689","05324562398" )             #musteri olustur
+account1 = Account(customer1, "TR12345", 1300)                                      #hesap olustur
+account1.display_information()                      #musteri bilgilerini gosterir
+customer1.display_information()