diff --git a/_collections/models.py b/_collections/models.py
deleted file mode 100644
index 5cd6efa..0000000
--- a/_collections/models.py
+++ /dev/null
@@ -1,23 +0,0 @@
-from fastapi import HTTPException
-from sqlalchemy import Column, Integer, String, Float, Boolean, ForeignKey
-from sqlalchemy.dialects.postgresql import ARRAY
-from sqlalchemy.orm import Session, relationship
-from ..config import Base
-
-
-
-'''
-##### veri tabanı modelleri #####
-class Collections(Base):
-    __tablename__ = "collections_table"
-
-    collection_id = Column(Integer, index=True, primary_key=True , autoincrement=True)
-    user_id = Column(Integer, ForeignKey('users_table.user_id'), nullable=False)
-    visibility = Column(Boolean, default=True)
-    colllection_name = Column(String, default="No name")
-    collection_description = Column(String, default="No description")
-
-    # ilişkiler
-    user = relationship("DBUser", back_populates="user_collections")
-    items = relationship("Items", back_populates="collection", cascade="all, delete-orphan")
-'''
\ No newline at end of file
diff --git a/_collections/router.py b/_collections/router.py
deleted file mode 100644
index 72387ea..0000000
--- a/_collections/router.py
+++ /dev/null
@@ -1,8 +0,0 @@
-from fastapi import FastAPI, APIRouter
-
-router = APIRouter(
-    prefix="/collections",
-    tags=["collections"],
-    responses={404: {"description": "Not found"}},
-    dependencies=[],
-)
\ No newline at end of file
diff --git a/auth/models.py b/auth/models.py
index 6305dcc..d6233ee 100644
--- a/auth/models.py
+++ b/auth/models.py
@@ -1,17 +1,23 @@
 from enum import Enum
 import random
 import smtplib
-from backend.config import SECRET_KEY, ALGORITHM, ACCESS_TOKEN_EXPIRE_MINUTES ,pwd_context, get_session_db, Base
+from backend.config import SECRET_KEY, ALGORITHM, ACCESS_TOKEN_EXPIRE_MINUTES ,pwd_context, get_session_db, Base, user_collection
 from datetime import datetime, timedelta, timezone
 from pydantic import BaseModel
 from fastapi import Depends, HTTPException
 from typing import Annotated
 from fastapi.security import OAuth2PasswordBearer
 from pydantic.networks import EmailStr
-from sqlalchemy import Integer, DateTime
+from sqlalchemy import Integer, DateTime, ForeignKey
 from sqlalchemy.orm import Session, relationship, mapped_column, Mapped
 from sqlalchemy.dialects.postgresql import ARRAY
 from email.message import EmailMessage
+from typing import TYPE_CHECKING
+
+
+if TYPE_CHECKING:
+    from ..collectionObj.models import CollectionsDB #iç içe import döngüsünü önlemek için TYPE_CHECKING kullanıyoruz
+
 
 import jwt
 
@@ -61,6 +67,7 @@ class DBUser(Base):
     __tablename__ = "users_table"
 
     user_id: Mapped[int] = mapped_column(primary_key=True, index=True, autoincrement=True)
+    #collection_id : Mapped[list[int]] = mapped_column(Integer, ForeignKey("collections_table.collection_id"), nullable=True) # collection_id ile ilişki
     username : Mapped[str] = mapped_column(unique=True, index=True, nullable=False)
     email : Mapped[str] = mapped_column(unique=True, index=True, nullable=False)
     hashed_password : Mapped[str] = mapped_column(nullable=False)
@@ -69,10 +76,14 @@ class DBUser(Base):
     created_date : Mapped[datetime] = mapped_column(DateTime, default=datetime.now()) #datetime.datetime -> python,   DateTime -> sqlalchemy
     bio : Mapped[str] = mapped_column(default="No bio")
     follow_users : Mapped[list[int]] = mapped_column(ARRAY(Integer), default=[]) # takip edilen kullanıcılar
-
     # -> buralar diğer tablolar ile olan ilişkiler
-    from ..items.models import Items
-    items : Mapped[list['Items']] = relationship("Items", back_populates="user", cascade="all, delete-orphan", lazy='select')
+    #items : Mapped[list['Items']] = relationship("Items", back_populates="user", cascade="all, delete-orphan") items'e direk değil collection üzerinden erişiyoruz
+    collections : Mapped[list['CollectionsDB']] = relationship(
+        "CollectionsDB", 
+        secondary=user_collection,
+        back_populates="users", 
+        lazy='select'
+    ) # collection'lar ile olan ilişki
 
 
 
@@ -128,7 +139,7 @@ async def get_current_user(
 
     credentials_exception = HTTPException(
         status_code=401,
-        detail="Invalid credentials",
+        detail="Invalid credentials currently",
         headers={"WWW-Authenticate": "Bearer"},
     )
     try:
diff --git a/collectionObj/models.py b/collectionObj/models.py
new file mode 100644
index 0000000..5ddc1d7
--- /dev/null
+++ b/collectionObj/models.py
@@ -0,0 +1,173 @@
+from fastapi import HTTPException, Depends
+from sqlalchemy import Integer, String, Boolean
+from pydantic import BaseModel
+from sqlalchemy.orm import Session, relationship, mapped_column, Mapped
+from ..config import Base, get_session_db, user_collection, collection_item
+from ..auth.models import DBUser
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from ..items.models import Items, Item
+    
+    
+
+
+###### SCHEMAS #########
+
+class CollectionBase(BaseModel):
+    collection_name : str | None = None
+    collection_description : str | None = None
+    visibility : bool | None = None
+
+class CollectionCreate(CollectionBase):
+    pass
+
+class CollectionPublic(CollectionBase):
+    collection_id : int | None = None
+
+    class Config:
+        from_attributes = True #sqlalchemy ile pydantic arasında geçiş yapabilmek için kullanılır
+
+class CollectionUpdate(CollectionBase):
+    pass
+
+    
+
+##### veri tabanı modelleri #####
+class CollectionsDB(Base):
+    __tablename__ = "collections_table"
+
+    collection_id : Mapped[int] = mapped_column(Integer, primary_key=True, index=True, autoincrement=True)
+    #user_id : Mapped[int] = mapped_column(Integer, ForeignKey("users_table.user_id"), nullable=False) # user_id ile ilişki
+    #item_id : Mapped[list[int]] = mapped_column(Integer, ForeignKey("items_table.item_id"), nullable=False) # item_id ile ilişki
+    visibility : Mapped[bool] = mapped_column(Boolean, default=True)
+    collection_name : Mapped[str] = mapped_column(String, nullable=False)
+    collection_description : Mapped[str] = mapped_column(String, default="No description")
+
+    # ilişkiler
+    users : Mapped[list['DBUser']] = relationship(
+        "DBUser",
+        secondary=user_collection, 
+        back_populates="collections", 
+        lazy='select'
+    ) #back_populates karşı tarafın ismi
+
+    items : Mapped[list['Items']] = relationship(
+        "Items",
+        secondary=collection_item,
+        back_populates="collections" ,
+        lazy='select'
+    )
+
+
+    #### collection bir item listesi birde kullanıcı listesi tutacak 
+
+
+
+def create_colletion(
+        collection: CollectionCreate | None = None,
+        user_id : int | None = None
+
+) -> bool:
+    """
+    Collection oluşturma fonksiyonu
+    """
+    if collection is None:
+        raise HTTPException(status_code=400, detail="Collection is None returned")
+    
+    session = next(get_session_db()) # -> get_session_db() fonksiyonu daima generator döndürür next ile çağırmalısın
+    user = session.query(DBUser).filter(DBUser.user_id == user_id).first()
+    if user is None:
+        raise HTTPException(status_code=404, detail="User not found")
+    
+
+    try: 
+        new_collection = CollectionsDB(
+            collection_name=collection.collection_name,
+            collection_description=collection.collection_description,
+            visibility=collection.visibility
+        )
+
+        new_collection.users.append(user)
+        session.add(new_collection)
+        session.commit()
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Error creating collection: {e}")
+    
+    return True
+
+
+def get_collections(
+        user_id : int | None = None
+) -> list[CollectionPublic] | None:
+    """
+    Kullanıcının collectionlarını döndürür
+    """
+    if user_id is None:
+        raise HTTPException(status_code=400, detail="User id is None")
+    
+    session = next(get_session_db()) # -> get_session_db() fonksiyonu daima generator döndürür next ile çağırmalısın
+    collections = session.query(CollectionsDB).filter(CollectionsDB.users.any(user_id=user_id)).all()
+    
+    if collections is None:
+        raise HTTPException(status_code=404, detail="No collections found")
+    
+    return collections
+
+def update_collection(
+        collection: CollectionUpdate | None = None,
+        user_id : int | None = None,
+        collection_id : int | None = None
+) -> bool:
+    """
+    Collection güncelleme fonksiyonu
+    """
+    if collection is None:
+        raise HTTPException(status_code=400, detail="Collection is None returned")
+    
+    session = next(get_session_db()) # -> get_session_db() fonksiyonu daima generator döndürür next ile çağırmalısın
+    user = session.query(DBUser).filter(DBUser.user_id == user_id).first()
+    if user is None:
+        raise HTTPException(status_code=404, detail="User not found")
+    
+    collection_to_update = session.query(CollectionsDB).filter(CollectionsDB.collection_id == collection_id).first()
+    if collection_to_update is None:
+        raise HTTPException(status_code=404, detail="Collection not found")
+    
+    try:
+        collection_to_update.collection_name = collection.collection_name
+        collection_to_update.collection_description = collection.collection_description
+        collection_to_update.visibility = collection.visibility
+
+        session.commit()
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Error updating collection: {e}")
+    
+    return True
+
+def delete_collection(
+        user_id : int | None = None,
+        collection_id : int | None = None
+) -> bool:
+    """
+    Collection silme fonksiyonu
+    """
+    if user_id is None or collection_id is None:
+        raise HTTPException(status_code=400, detail="User id or collection id is None")
+    
+    session = next(get_session_db()) # -> get_session_db() fonksiyonu daima generator döndürür next ile çağırmalısın
+    user = session.query(DBUser).filter(DBUser.user_id == user_id).first()
+    if user is None:
+        raise HTTPException(status_code=404, detail="User not found")
+    
+    collection_to_delete = session.query(CollectionsDB).filter(CollectionsDB.collection_id == collection_id).first()
+    if collection_to_delete is None:
+        raise HTTPException(status_code=404, detail="Collection not found")
+    
+    try:
+        session.delete(collection_to_delete)
+        session.commit()
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Error deleting collection: {e}")
+    
+    return True
\ No newline at end of file
diff --git a/collectionObj/router.py b/collectionObj/router.py
new file mode 100644
index 0000000..f258273
--- /dev/null
+++ b/collectionObj/router.py
@@ -0,0 +1,60 @@
+from fastapi import FastAPI, APIRouter
+from .models import CollectionPublic, CollectionCreate, CollectionUpdate
+from .models import get_collections, create_colletion, update_collection, delete_collection
+
+router = APIRouter(
+    prefix="/collections",
+    tags=["collections"],
+    responses={404: {"description": "Not found"}},
+    dependencies=[],
+)
+
+
+
+@router.get("/{user_id}")
+async def get_collections_api(user_id: int) -> list[CollectionPublic]:
+    """
+    Kullanıcının collectionlarını döndürür
+    """
+
+    _collections : list[CollectionPublic] = get_collections(user_id=user_id)
+
+    return _collections
+
+
+
+@router.post("/{user_id}")
+async def create_collection(
+    user_id: int,
+    collection: CollectionCreate
+) -> bool:
+    """
+    Collection oluşturma fonksiyonu
+    """
+    _result = create_colletion(user_id=user_id, collection=collection)
+    return _result
+
+
+@router.put("/{user_id}/{collection_id}")
+async def update_collection_api(
+    user_id: int,
+    collection_id : int,
+    collection: CollectionUpdate
+) -> bool:
+    """
+    Collection güncelleme fonksiyonu
+    """
+    _result = update_collection(user_id=user_id, collection_id=collection_id, collection=collection)
+    return _result
+
+
+@router.delete("/{user_id}/{collection_id}")
+async def delete_collection_api(
+    user_id: int,
+    collection_id : int
+) -> bool:
+    """
+    Collection silme fonksiyonu
+    """
+    _result = delete_collection(user_id=user_id, collection_id=collection_id)
+    return _result
\ No newline at end of file
diff --git a/config.py b/config.py
index 40dc1d9..9657ba7 100644
--- a/config.py
+++ b/config.py
@@ -2,6 +2,7 @@ from sqlalchemy import create_engine
 from sqlalchemy.orm import sessionmaker, DeclarativeBase
 from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
+from sqlalchemy import Table, Column, Integer, String, Float, Boolean, ForeignKey
 from passlib.context import CryptContext
 from dotenv import load_dotenv
 import os
@@ -30,16 +31,31 @@ class Base(DeclarativeBase):
 
 def init_db():
     #Base.metadata.drop_all(engine)   # Veritabanını her başlangıcta siler burayada dikkat !!!!!!!!
-    Base.metadata.create_all(bind=engine)
+    Base.metadata.create_all(bind=engine) # Veritabanını oluşturur
 
 # Session dependency (FastAPI için)
-def get_session_db():
+def get_session_db() -> 'Generator[Session, None]':
     db = SessionLocal()
     try:
         yield db
     finally:
         db.close()
 
+user_collection = Table(   # user -> collection
+    "user_collection",
+    Base.metadata,
+    Column("user_id", Integer, ForeignKey("users_table.user_id"), primary_key=True),
+    Column("collection_id", Integer, ForeignKey("collections_table.collection_id"), primary_key=True),
+)
+
+
+collection_item = Table(   # collection -> item
+    "collection_item",
+    Base.metadata,
+    Column("collection_id", ForeignKey("collections_table.collection_id"), primary_key=True),
+    Column("item_id", ForeignKey("items_table.item_id"), primary_key=True)
+)
+
 
 
 ### SECRET KEY ###
diff --git a/items/models.py b/items/models.py
index 220ba7d..9adbf6d 100644
--- a/items/models.py
+++ b/items/models.py
@@ -1,18 +1,15 @@
 from datetime import datetime, timedelta, timezone
 from typing import Annotated
-
 from sqlalchemy import DateTime
 from pydantic import BaseModel
 from fastapi import Depends
 from sqlalchemy.orm import Session, relationship, mapped_column, Mapped
-from sqlalchemy import ForeignKey, Column, Integer, String, Float
+from sqlalchemy import String, Float, Integer, ForeignKey
 from sqlalchemy.dialects.postgresql import ARRAY
-from ..config import Base, get_session_db
+from ..config import Base, get_session_db, collection_item
 from typing import TYPE_CHECKING
 from ..auth.models import Role, Status, UserBase
-
-####!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-from ..auth.models import DBUser # -> tam burda bir hata var circle import yaparken karışıyor nasıl çözülecek bilmiyorum
+from ..collectionObj.models import CollectionsDB
 
 
 class UserProfileBase(UserBase): 
@@ -28,10 +25,11 @@ class UserProfilePublic(UserProfileBase):
     pass
 
 class UserProfilePrivate(UserProfilePublic):
-    collection : list[str] | None = None
+    #collection : list[str] | None = None
     role : Role | None = None
     status : Status | None = None
     follow_user : list[int] | None = None
+    items : list['Item'] | None = None
 
 
 
@@ -46,66 +44,35 @@ class BaseItem(BaseModel):
 class ItemCreate(BaseItem): # item oluşturma için ekstra bir ihtiyaci olmaz 
     pass
 
+
+class Item(BaseItem):
+    item_id : int | None = None
+    user_id : int | None = None
+    item_score : float | None = None
+
+    class Config:
+        from_attributes = True #sqlalchemy ile pydantic arasında geçiş yapabilmek için kullanılır
+
 ##### VERİTABANI MODELİ #####
 # Tüm modeller AUTH'da veri tabanına işlendi yukardaki
 #modeller veri tabanında mevcuttur. Değiştirmek için AUTH'daki
 # DBUser modelini değiştirip tekrar veri tabanına işleyebilirsin
-'''
-'''
+
 class Items(Base):
     __tablename__ = "items_table"
 
     item_id : Mapped[int] = mapped_column(primary_key=True, index=True, autoincrement=True)
-    user_id : Mapped[int] = mapped_column(ForeignKey('users_table.user_id'), nullable=False, index=True)
+    #collection_id : Mapped[list[int]] = mapped_column(Integer, ForeignKey("collections_table.collection_id"), nullable=True) # collection_id ile ilişki
     item_created_date : Mapped[datetime] = mapped_column(DateTime, default=datetime.now())
-    item_location = Column(String, default="No location")
-    item_type = Column(String, default="No type")
-    item_content = Column(String, default="No content")
-    item_score = Column(Float, default=0.0)
+    item_location: Mapped[str] = mapped_column(String, default="No location")
+    item_type: Mapped[str] = mapped_column(String, default="No type")
+    item_content: Mapped[str] = mapped_column(String, default="No content")
+    item_score: Mapped[float] = mapped_column(Float, default=0.0)
 
-    # ilişkiler
-    
-    user : Mapped['DBUser'] = relationship("DBUser", back_populates="items", lazy='select')
-    #collection = relationship("Collections", back_populates="items")
-    
-    
-'''
-'''
-def is_user_exsist(username : str, session : Annotated[Session, Depends(get_session_db)]) -> bool | UserProfilePublic:
-     #DBUser veritabanındaki nesnedir her niteliğe sahiptir
-    user = session.query(DBUser).filter(DBUser.username == username).first()
-    return user
-
-
-def all_users(session: Annotated[Session, Depends(get_session_db)]) -> list[UserProfilePublic]:
-    users = session.query(DBUser).all()
-
-    return [UserProfilePublic(
-        username=user.username,
-        bio=user.bio,
-        created_date=user.created_date,
-        items=user.items,
-        collections=user.collections,
-        role=user.role,
-        status=user.status
-    ) for user in users]
-
-
-def add_Item_user(
-        user: Annotated[UserProfileID, Depends(get_session_db)], 
-        session: Annotated[Session, Depends(get_session_db)],
-        item: ItemCreate) -> bool:
-    # DBUser veritabanındaki nesnedir her niteliğe sahiptir
-
-    item = Items(
-        user_id=user.user_id,
-        item_location=item.item_location,
-        item_type=item.item_type,
-        item_content=item.item_content,
-        item_score=item.item_score,
-        item_created_date=item.item_created_date
-    )
-
-    session.add(item)
-    session.commit()
-    return True
+    # ilişkiler 
+    collections : Mapped[list['CollectionsDB']]= relationship(
+        "CollectionsDB",
+        secondary=collection_item,
+        back_populates="items", 
+        lazy='select'
+    )  #back_populates karşı tarafın ismi
diff --git a/items/router.py b/items/router.py
index f2e4718..8704d2b 100644
--- a/items/router.py
+++ b/items/router.py
@@ -1,4 +1,4 @@
-from .models import ItemCreate, UserProfileBase, UserProfileID, UserProfilePrivate, UserProfilePublic, add_Item_user, all_users, is_user_exsist
+from .models import ItemCreate, UserProfileBase, UserProfileID, UserProfilePrivate, UserProfilePublic
 from fastapi import APIRouter, Depends
 from sqlalchemy.orm import Session
 from ..config import get_session_db
@@ -12,43 +12,7 @@ router = APIRouter(
     dependencies=[],
 )
 
-@router.get('/all_profiles')
-async def get_user_profile(session: Annotated[Session, Depends(get_session_db)]) -> list[UserProfilePublic]:
-    
-    return all_users(session=session)
-
-
-@router.get('/profile/{username}')
-async def get_user_profile_by_username(
-    username: str,
-    session: Annotated[Session, Depends(get_session_db)],
-) -> UserProfilePublic | dict:
-    
-    user : UserProfilePublic = is_user_exsist(username, session)
-    if user is None:
-        return {"error": "User not found"}
-    
-    return user
-
-@router.get('/profile/me')
-async def get_user_profile_me(
-    current_user: Annotated[UserProfilePrivate, Depends(get_current_active_user)] #dependtek kaynaklı UserPublic doner
-    ) -> UserProfilePrivate:
-    
-    return current_user
-    
-
-@router.post('/create')
-async def create_user_profile(
-    user : Annotated[UserProfileID, Depends(get_current_active_user)],
-    session: Annotated[Session, Depends(get_session_db)],
-    item : Annotated[ItemCreate , None] = None
-) -> dict:
-    
-    if add_Item_user(user, session, item) :
-        return {"message": "User item created successfully"}
-    
-    return {"error": "User item creation failed"}
+#tüm crud işlemleri yeni veri tabanı modeli ile yapılacak
 
 
 
diff --git a/main.py b/main.py
index 93010c6..9415e73 100644
--- a/main.py
+++ b/main.py
@@ -1,7 +1,7 @@
 from .config import app
 from .auth.router import router as auth_router
 from .items.router import router as items_router
-from ._collections.router import router as collections_router
+from .collectionObj.router import router as collections_router
 
 app.include_router(auth_router)
 app.include_router(collections_router)