diff --git a/entity.py b/entity.py
index ef22087..75515a6 100644
--- a/entity.py
+++ b/entity.py
@@ -1,7 +1,20 @@
 from .serializable import Serializable
+from enum import Enum, IntEnum
+
+class Action(Enum):
+    ATTACK = 'strength' # Physical Battle action
+    FORCE = 'strength' # Actions that requires physical effort
+    SPELL = 'intelligence' # Many kind of spell (battle or not)
+    SCAN = 'wisdom' # Danger in environment or NPC's lies
+    SPEECH = 'charisma' # To persuade or deceive
+    AGILE = 'dexterity' # Avoid traps or incoming attacks & spell
+
+class BonusAction(IntEnum):
+    EQUIP_ITEM = 0
+    USE_CONSUMMABLE = 1
 
 class Entity(Serializable):
-    def __init__(self, name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed):
+    def __init__(self, name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed, equipped_item=None):
         self.name =name
         self.strength = strength
         self.dexterity = dexterity
@@ -10,4 +23,8 @@ class Entity(Serializable):
         self.charisma = charisma
         self.hp =hp
         self.armor = armor
-        self.speed = speed
\ No newline at end of file
+        self.speed = speed
+        self.equipped_item = equipped_item
+    
+    def make_a_turn(self, action:Action, bonus_action:BonusAction):
+        pass
\ No newline at end of file
diff --git a/inventory.py b/inventory.py
index 0ae1030..07f7799 100644
--- a/inventory.py
+++ b/inventory.py
@@ -1,5 +1,31 @@
 from .serializable import Serializable
+from .item import Item
 
 class Inventory(Serializable):
-    def __init__(self):
-        super().__init__()
\ No newline at end of file
+    def __init__(self, max_capacity:float = 50.0):
+        super().__init__()
+        self.items:list[Item] = []
+        self.max_capacity = max_capacity # Weight (kg)
+    
+    def current_capacity(self):
+        return sum([item.weight for item in self.items])
+
+    def list_items(self):
+        s_items = ''
+        for item in self.items:
+            s_items += item.__str__() + '; '
+        return s_items
+
+    def add_item(self, added_item:Item):
+        if added_item.weight + self.current_capacity() > self.max_capacity:
+            return f'{added_item.name} is too heavy to fit inside the inventory: {added_item.weight + self.current_capacity() - self.max_capacity}kg in surplus!'
+        else:
+            self.items.append(added_item)
+            return f'{added_item.name} added to inventory. Current items load: {self.current_capacity()}kg'
+    
+    def remove_item(self, r_item):
+        if r_item in self.items:
+            self.items.remove(r_item)
+            return f'{r_item.name} was removed from the inventory'
+        else:
+            return f'{r_item.name} is not present within the inventory'
\ No newline at end of file
diff --git a/item.py b/item.py
index aefbd56..7abb753 100644
--- a/item.py
+++ b/item.py
@@ -1,5 +1,11 @@
 from .serializable import Serializable
 
 class Item(Serializable):
-    def __init__(self):
-        super().__init__()
\ No newline at end of file
+    def __init__(self,name:str, description:str, weight:float = 10.0):
+        super().__init__()
+        self.name = name
+        self.description = description
+        self.weight = weight
+    
+    def __str__(self):
+        return self.name + '(' + self.weight + ' kg)' + ': ' + self.description
\ No newline at end of file
diff --git a/npc.py b/npc.py
index 6ab6f9a..0602f8d 100644
--- a/npc.py
+++ b/npc.py
@@ -1,6 +1,5 @@
 from .entity import Entity
 
 class NPC(Entity):
-    def __init__(self, name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed, item=None):
-        super().__init__(name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed)
-        self.item = item
\ No newline at end of file
+    def __init__(self, name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed, equipped_item=None):
+        super().__init__(name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed, equipped_item)
\ No newline at end of file
diff --git a/player.py b/player.py
index 6a05bcd..9d758b7 100644
--- a/player.py
+++ b/player.py
@@ -1,6 +1,7 @@
 from .entity import Entity
+from .inventory import Inventory
 
 class Player(Entity):
-    def __init__(self, name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed, item=None):
-        super().__init__(name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed)
-        self.item = item
\ No newline at end of file
+    def __init__(self, name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed, equipped_item=None):
+        super().__init__(name, strength, dexterity, intelligence, wisdom, charisma, hp, armor, speed, equipped_item)
+        self.inventory = Inventory(max_capacity=50)
\ No newline at end of file