diff --git a/__pycache__/database.cpython-310.pyc b/__pycache__/database.cpython-310.pyc
index bea0111..76694da 100644
Binary files a/__pycache__/database.cpython-310.pyc and b/__pycache__/database.cpython-310.pyc differ
diff --git a/article.py b/article.py
new file mode 100644
index 0000000..b7f97a2
--- /dev/null
+++ b/article.py
@@ -0,0 +1,26 @@
+class Article():
+    def __init__(self, name: str, id: str, price: float = 0, quantity: int = 1) -> Article:
+        """
+        the article data
+        :param name: the name
+        :type name: str
+        :param id: uuid
+        :type id: str
+        :param price: price
+        :type price: float
+        :param quantity: quantity
+        :type quantity: int
+        :return: the article
+        :rtype: Article
+        """
+        self.name = name;
+        self.id = id;
+        self.price = price;
+        self.quantity = quantity;
+        return (self);
+
+    def __repr__(self):
+        return (f"Article(name={self.name},id={self.id},price={self.price},quantity={self.quantity})")
+
+    def __str__(self):
+        return (self.__repr__())
diff --git a/database.json b/database.json
deleted file mode 100644
index 33f2594..0000000
--- a/database.json
+++ /dev/null
@@ -1,14 +0,0 @@
-{
-    "users": {
-        "1": {
-            "email": "camille@chauvet.pro",
-            "password": "b'$2b$12$FVOKVF9p/SlSv9ANVNDW.eOmv1f3qtB0WU86g4ED4B8J2fMBPZu7.'"
-        },
-        "2": {
-            "email": "spam@camille.chauvet.pro",
-            "password": "b'$2b$12$D2DexgunhMTbYWkXmEQKw.Aa13W9QZE4CjsNUyaU5bSaZ8ZpdJ2hO'"
-        }
-    },
-    "resets": {},
-    "_default": {}
-}
\ No newline at end of file
diff --git a/database.py b/database.py
index 4455776..05a73b7 100644
--- a/database.py
+++ b/database.py
@@ -24,7 +24,7 @@ def user_exist(email: str):
 
 def add_user(email: str, password: str):
     password_hashed = hasher.hash_text(password)
-    users.insert({"email": email, "password": str(password_hashed)});
+    users.insert({"email": email, "password": str(password_hashed), "id": uuid.uuid4()});
 
 def check_password(email: str, password: str):
     password_hashed = get_user_by_email(email).get("password")
diff --git a/grocery_list.py b/grocery_list.py
new file mode 100644
index 0000000..0ded30c
--- /dev/null
+++ b/grocery_list.py
@@ -0,0 +1,12 @@
+class GroceryList():
+    def __init__(self, id: str, articles: list):
+        """
+        Groceries List
+        :param id: uuid
+        :type id: str
+        :param articles: list of articles
+        :type articles: list[Article]
+        :return: the grocery list
+        :rtype: GroceryList
+        """
+        self.id = str
diff --git a/group.py b/group.py
new file mode 100644
index 0000000..5065d1d
--- /dev/null
+++ b/group.py
@@ -0,0 +1,23 @@
+class Group():
+    def __init__(self, id: str, members: list, lists: list) -> Group:
+        """
+        this class aims to store group with an id, a list of members, a lists of greceries lists
+        :param id: the uuid of the groups
+        :type id: int
+        :param members: the lists of members (User)
+        :type members: list[User]
+        :param lists: the lists of groceries lists
+        :type lists: list[GroceriesList]
+        :return: the group
+        :rtype: Group
+        """
+        self.id = id;
+        self.members = members
+        self.lists: lists
+        return (self)
+
+    def __str__(self):
+        return (f"Group(id={self.id},members={self.members},lists={self.lists})")
+
+    def __repr__(self):
+        return (self.__str__())
diff --git a/user.py b/user.py
new file mode 100644
index 0000000..0b0a70c
--- /dev/null
+++ b/user.py
@@ -0,0 +1,25 @@
+class User():
+    def __init__(self, mail: str, password: str, id: str, groups: list = []) -> User:
+        """
+        User: store user data
+        :param mail: the mail address
+        :type mail: str
+        :param password: the password
+        :type password: str
+        :param id: the uuid
+        :type id: str
+        :param groups: the lists of groups the user is in
+        :type groups: list[Group]
+        :return: the user
+        :rtype: User
+        """
+        self.mail = mail
+        self.password = password
+        self.id = id;
+        self.groups = groups
+
+    def __repr__(self):
+        return (f"User(mail={self.mail},password={self.password},id={self.id},groups={self.groups})")
+
+    def __str__(self):
+        return (self.__repr__())