diff --git a/.gitignore b/.gitignore
index 4a3a6d3..6c1ac87 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,6 +4,9 @@
 ##
 ## Get latest from https://github.com/github/gitignore/blob/main/VisualStudio.gitignore
 
+# User-spacific editor config
+.editorconfig
+
 # User-specific files
 *.rsuser
 *.suo
diff --git a/MCTG/MCTGApp/MCTGApp.csproj b/MCTG/ConsoleApp/ConsoleApp.csproj
similarity index 73%
rename from MCTG/MCTGApp/MCTGApp.csproj
rename to MCTG/ConsoleApp/ConsoleApp.csproj
index f02677b..c7f3ecd 100644
--- a/MCTG/MCTGApp/MCTGApp.csproj
+++ b/MCTG/ConsoleApp/ConsoleApp.csproj
@@ -7,4 +7,8 @@
     <Nullable>enable</Nullable>
   </PropertyGroup>
 
+  <ItemGroup>
+    <ProjectReference Include="..\Model\Model.csproj" />
+  </ItemGroup>
+
 </Project>
diff --git a/MCTG/ConsoleApp/Program.cs b/MCTG/ConsoleApp/Program.cs
new file mode 100644
index 0000000..773f61b
--- /dev/null
+++ b/MCTG/ConsoleApp/Program.cs
@@ -0,0 +1,21 @@
+// See https://aka.ms/new-console-template for more information
+
+using ConsoleApp;
+using Model;
+
+
+Console.WriteLine("Hello, World!\n\n");
+
+
+// TESTS:
+
+Stub stub = new Stub();
+
+List<Recipe> recipes = stub.LoadRecipes();
+List<RecipeCollection> recipeCollections = stub.LoadRecipeCollection();
+
+foreach (Recipe r in recipes)
+    Console.WriteLine(r);
+
+foreach (RecipeCollection r in recipeCollections)
+    Console.WriteLine(r);
diff --git a/MCTG/ConsoleApp/Stub.cs b/MCTG/ConsoleApp/Stub.cs
new file mode 100644
index 0000000..a6fc02a
--- /dev/null
+++ b/MCTG/ConsoleApp/Stub.cs
@@ -0,0 +1,45 @@
+using Model;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace ConsoleApp
+{
+    internal struct Stub
+    {
+        public List<Recipe> LoadRecipes()
+        {
+            List<Recipe> stub = new List<Recipe>();
+            stub.AddRange(new[]
+            {
+                new Recipe(),
+                new Recipe("Cookies"),
+                new Recipe("Cookies", 23),
+                new Recipe("Cookies", null),
+                new Recipe("", null),
+                new Recipe("", 24),
+                new Recipe("Cookies", 24,
+                    new PreparationStep(1)),
+                new Recipe("Cookies", 26,
+                    new PreparationStep(1),
+                    new PreparationStep(2, "Faire cuire."))
+            });
+            return stub;
+        }
+
+        public List<RecipeCollection> LoadRecipeCollection()
+        {
+            List<RecipeCollection> stub = new List<RecipeCollection>();
+            stub.AddRange(new[]
+            {
+                new RecipeCollection("All", LoadRecipes().ToArray()),
+                new RecipeCollection("Starters", LoadRecipes().FindAll(x => x.Id.Equals(23)).ToArray()),
+                new RecipeCollection("Dishies", LoadRecipes().FindAll(x => x.Id.Equals(24)).ToArray()),
+                new RecipeCollection("Desserts", LoadRecipes().FindAll(x => x.Id.Equals(26)).ToArray()),
+            });
+            return stub;
+        }
+    }
+}
diff --git a/MCTG/MCTGApp/Program.cs b/MCTG/MCTGApp/Program.cs
deleted file mode 100644
index 3751555..0000000
--- a/MCTG/MCTGApp/Program.cs
+++ /dev/null
@@ -1,2 +0,0 @@
-// See https://aka.ms/new-console-template for more information
-Console.WriteLine("Hello, World!");
diff --git a/MCTG/MCTGLib/Class1.cs b/MCTG/MCTGLib/Class1.cs
deleted file mode 100644
index 5b51184..0000000
--- a/MCTG/MCTGLib/Class1.cs
+++ /dev/null
@@ -1,7 +0,0 @@
-namespace MCTGLib
-{
-    public class Class1
-    {
-
-    }
-}
\ No newline at end of file
diff --git a/MCTG/MCTGLib/MCTGLib.csproj b/MCTG/Model/Model.csproj
similarity index 100%
rename from MCTG/MCTGLib/MCTGLib.csproj
rename to MCTG/Model/Model.csproj
diff --git a/MCTG/Model/PreparationStep.cs b/MCTG/Model/PreparationStep.cs
new file mode 100644
index 0000000..95d15ca
--- /dev/null
+++ b/MCTG/Model/PreparationStep.cs
@@ -0,0 +1,80 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Model
+{
+    /// <summary>
+    /// Define a step of the preparation of a recipe.
+    /// </summary>
+    public class PreparationStep : IEquatable<PreparationStep>
+    {
+        #region Attributes
+        private string _description = "";
+        #endregion
+
+        #region Properties
+        /// <summary>
+        /// The order of this step in the preparation of the meal.
+        /// </summary>
+        public int Order { get; init; }
+
+        /// <summary>
+        /// The description of the task the user need to do for this step of the preparation. <br/>
+        /// Set to "No description." when the value passed is null, empty or contain white spaces.
+        /// </summary>
+        public string Description
+        {
+            get => _description;
+            private set
+            {
+                if (string.IsNullOrWhiteSpace(value))
+                    _description = "No description.";
+                else
+                    _description = value;
+            }
+        }
+        #endregion
+
+        #region Constructors
+        /// <summary>
+        /// Construct a new step of preparation.
+        /// </summary>
+        /// <param name="order">The number of the order in preparation</param>
+        /// <param name="description">The description of the task</param>
+        public PreparationStep(int order, string description = "")
+        {
+            Order = order;
+            Description = description;
+        }
+        #endregion
+
+        #region Methods
+        public virtual bool Equals(PreparationStep? other)
+        {
+            if (other == null) return false;
+            if (other == this) return true;
+            return Order.Equals(other.Order) && Description.Equals(other.Description);
+        }
+
+        public override bool Equals(object? obj)
+        {
+            var item = obj as PreparationStep;
+            if (item == null) return false;
+            return Equals(obj);
+        }
+
+        public override int GetHashCode()
+        {
+            return Order.GetHashCode() + Description.GetHashCode();
+        }
+
+        public override string ToString()
+        {
+            return $"{Order}- {Description}";
+        }
+        #endregion
+    }
+}
diff --git a/MCTG/Model/Recipe.cs b/MCTG/Model/Recipe.cs
new file mode 100644
index 0000000..9d65bf9
--- /dev/null
+++ b/MCTG/Model/Recipe.cs
@@ -0,0 +1,101 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace Model
+{
+    /// <summary>
+    /// Define a Recipe for the preparation of a meal.
+    /// </summary>
+    public class Recipe : IEquatable<Recipe>
+    {
+        #region Attributes
+        private string _title = "";
+        #endregion
+
+        #region Properties
+        /// <summary>
+        /// The ID of the recipe - allows you to compare and/or get this item in an easier way.
+        /// </summary>
+        public int Id { get; init; }
+
+        /// <summary>
+        /// The Title of the recipe. <br/>
+        /// Set to "No title." when the value passed is null, empty or contain white spaces.
+        /// </summary>
+        public string Title
+        {
+            get => _title;
+            set
+            {
+                if (string.IsNullOrWhiteSpace(value))
+                    _title = "No title.";
+                else
+                    _title = value;
+            }
+        }
+
+        /// <summary>
+        /// The steps of the preparation. See: <see cref="PreparationStep"/>.
+        /// </summary>
+        public List<PreparationStep> PreparationSteps { get; set; }
+        #endregion
+
+        #region Constructors
+        /// <summary>
+        /// Construct a new recipe.
+        /// </summary>
+        /// <param name="title">The title of the recipe</param>
+        /// <param name="id">The id of the recipe. If not given, get a new id.</param>
+        /// <param name="preparationSteps">The steps of the preparation of the meal</param>
+        public Recipe(string title = "", int? id = null,
+                      params PreparationStep[] preparationSteps)
+        {
+            Title = title;
+            PreparationSteps = new List<PreparationStep>(preparationSteps);
+
+            if (id == null)
+            {
+                var randomGenerator = RandomNumberGenerator.Create();
+                byte[] data = new byte[16];
+                randomGenerator.GetBytes(data);
+                Id = Math.Abs(BitConverter.ToInt16(data));
+            }
+            else Id = (int)id;
+        }
+        #endregion
+
+        #region Methods
+        public virtual bool Equals(Recipe? other)
+        {
+            if (other == null) return false;
+            if (other == this) return true;
+            return Title.Equals(other.Title) && PreparationSteps.Equals(other.PreparationSteps);
+        }
+
+        public override bool Equals(object? obj)
+        {
+            var item = obj as Recipe;
+            if (item == null) return false;
+            return Equals(obj);
+        }
+
+        public override int GetHashCode()
+        {
+            return Id.GetHashCode();
+        }
+
+        public override string ToString()
+        {
+            StringBuilder sb = new StringBuilder($"[Recipe n°{Id}] - {Title}\n");
+            foreach (PreparationStep ps in PreparationSteps)
+            {
+                sb.AppendFormat("\t* {0}\n", ps.ToString());
+            }
+            return sb.ToString();
+        }
+        #endregion
+    }
+}
diff --git a/MCTG/Model/RecipeCollection.cs b/MCTG/Model/RecipeCollection.cs
new file mode 100644
index 0000000..3592bb8
--- /dev/null
+++ b/MCTG/Model/RecipeCollection.cs
@@ -0,0 +1,154 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Text;
+
+namespace Model
+{
+    /// <summary>
+    /// Define a collection of <see cref="Recipe"/>.
+    /// <br/>This class implement <see cref="IList"/> and <see cref="IEquatable{T}"/>.
+    /// </summary>
+    public class RecipeCollection : IList<Recipe>, IEquatable<RecipeCollection>
+    {
+        #region Attributes
+        private readonly List<Recipe> _recipes;
+        private string _description = "";
+        #endregion
+
+        #region Properties
+        /// <summary>
+        /// A short description of what this collection contain. <br/>
+        /// Set to "No description." when the value passed is null, empty or contain white spaces.
+        /// </summary>
+        public string Description
+        {
+            get => _description;
+            set
+            {
+                if (string.IsNullOrWhiteSpace(value))
+                    _description = "No description.";
+                else
+                    _description = value;
+            }
+        }
+
+        #region IList Prperties
+        public int Count => _recipes.Count;
+        public bool IsReadOnly => false;
+        public Recipe this[int index] { get => _recipes[index]; set => _recipes[index] = value; }
+        #endregion
+        #endregion
+
+        #region Constructors
+        /// <summary>
+        /// Construct a new collection of _recipes.
+        /// </summary>
+        /// <param name="description">A short description of what this list will contain</param>
+        /// <param name="recipes">Recipes to add in this new collection</param>
+        public RecipeCollection(string description, params Recipe[] recipes)
+        {
+            _recipes = new List<Recipe>(recipes);
+            Description = description;
+        }
+        #endregion
+
+        #region Methods
+        /// <summary>
+        /// Find a recipe in this list by giving the id.
+        /// </summary>
+        /// <param name="id">The id of the list we are looking for</param>
+        /// <returns>The recipe of the id given</returns>
+        /// <exception cref="ArgumentException"/>
+        public Recipe? GetRecipeById(int id)
+        {
+            Recipe? recipe = _recipes.Find(r => r.Id == id);
+            if (recipe == null) throw new ArgumentException("No _recipes match the given id.");
+            return recipe;
+        }
+
+        #region IList Methods
+        public int IndexOf(Recipe item)
+        {
+            return _recipes.IndexOf(item);
+        }
+
+        public void Insert(int index, Recipe item)
+        {
+            _recipes.Insert(index, item);
+        }
+
+        public void RemoveAt(int index)
+        {
+            _recipes.RemoveAt(index);
+        }
+
+        public void Add(Recipe item)
+        {
+            _recipes.Add(item);
+        }
+
+        public void Clear()
+        {
+            _recipes.Clear();
+        }
+
+        public bool Contains(Recipe item)
+        {
+            return _recipes.Contains(item);
+        }
+
+        public void CopyTo(Recipe[] array, int arrayIndex)
+        {
+            _recipes.CopyTo(array, arrayIndex);
+        }
+
+        public bool Remove(Recipe item)
+        {
+            return _recipes.Remove(item);
+        }
+
+        public IEnumerator<Recipe> GetEnumerator()
+        {
+            return _recipes.GetEnumerator();
+        }
+
+        IEnumerator IEnumerable.GetEnumerator()
+        {
+            return _recipes.GetEnumerator();
+        }
+        #endregion
+
+        public virtual bool Equals(RecipeCollection? other)
+        {
+            
+            if (other == null) return false;
+            if (other == this) return true;
+            return _description.Equals(other.Description) && _recipes.Equals(other._recipes);
+        }
+
+        public override bool Equals(object? obj)
+        {
+            var item = obj as RecipeCollection;
+            if (item == null) return false;
+            return Equals(obj);
+        }
+
+        public override int GetHashCode()
+        {
+            return _recipes.GetHashCode();
+        }
+
+        public override string ToString()
+        {
+            StringBuilder sb = new StringBuilder($"[RecipeCollection] - {Description}:\n");
+            foreach (Recipe r in _recipes)
+            {
+                sb.AppendFormat("\t - {0}\n", r.ToString());
+            }
+            return sb.ToString();
+        }
+        #endregion
+    }
+}
diff --git a/MCTG/SAE-2.01.sln b/MCTG/SAE-2.01.sln
index ab7e910..81242a9 100644
--- a/MCTG/SAE-2.01.sln
+++ b/MCTG/SAE-2.01.sln
@@ -3,11 +3,11 @@ Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio Version 17
 VisualStudioVersion = 17.5.33516.290
 MinimumVisualStudioVersion = 10.0.40219.1
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MCTGApp", "MCTGApp\MCTGApp.csproj", "{666C2211-8EBB-4FC8-9484-CB93BC854153}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ConsoleApp", "ConsoleApp\ConsoleApp.csproj", "{666C2211-8EBB-4FC8-9484-CB93BC854153}"
 EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MCTGLib", "MCTGLib\MCTGLib.csproj", "{42FF86BD-92F9-4A32-A938-68515905378F}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Model", "Model\Model.csproj", "{42FF86BD-92F9-4A32-A938-68515905378F}"
 EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MCTGLib_UnitTests", "Tests\MCTGLib_UnitTests\MCTGLib_UnitTests.csproj", "{45AB746A-194B-4E43-81EB-83B06F35AA33}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Model_UnitTests", "Tests\Model_UnitTests\Model_UnitTests.csproj", "{45AB746A-194B-4E43-81EB-83B06F35AA33}"
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Tests", "Tests", "{08B80CE8-A01D-4D86-8989-AF225D5DA48C}"
 EndProject
diff --git a/MCTG/Tests/MCTGLib_UnitTests/UnitTest1.cs b/MCTG/Tests/MCTGLib_UnitTests/UnitTest1.cs
deleted file mode 100644
index 4d22b68..0000000
--- a/MCTG/Tests/MCTGLib_UnitTests/UnitTest1.cs
+++ /dev/null
@@ -1,11 +0,0 @@
-namespace MCTGLib_UnitTests
-{
-    public class UnitTest1
-    {
-        [Fact]
-        public void Test1()
-        {
-
-        }
-    }
-}
\ No newline at end of file
diff --git a/MCTG/Tests/MCTGLib_UnitTests/MCTGLib_UnitTests.csproj b/MCTG/Tests/Model_UnitTests/Model_UnitTests.csproj
similarity index 91%
rename from MCTG/Tests/MCTGLib_UnitTests/MCTGLib_UnitTests.csproj
rename to MCTG/Tests/Model_UnitTests/Model_UnitTests.csproj
index 42ff44d..dc31a95 100644
--- a/MCTG/Tests/MCTGLib_UnitTests/MCTGLib_UnitTests.csproj
+++ b/MCTG/Tests/Model_UnitTests/Model_UnitTests.csproj
@@ -22,4 +22,8 @@
     </PackageReference>
   </ItemGroup>
 
+  <ItemGroup>
+    <ProjectReference Include="..\..\Model\Model.csproj" />
+  </ItemGroup>
+
 </Project>
diff --git a/MCTG/Tests/Model_UnitTests/Recipe_UT.cs b/MCTG/Tests/Model_UnitTests/Recipe_UT.cs
new file mode 100644
index 0000000..e8593a5
--- /dev/null
+++ b/MCTG/Tests/Model_UnitTests/Recipe_UT.cs
@@ -0,0 +1,26 @@
+using Model;
+
+namespace Model_UnitTests
+{
+    public class Recipe_UT
+    {
+        [Fact]
+        public void TestVoidConstructor()
+        {
+            Recipe r = new Recipe(id: 999); // id is given to avoid tests errors with the static atrribute 'idCreator'.
+            Assert.NotNull(r.Title);
+        }
+
+        [Theory]
+        [InlineData("Cookies", 23, "Cookies", 23)]
+        [InlineData("Cookies", 1, "Cookies", 1)]
+        [InlineData("No title.", 1, "", 1)]
+        public void TestConstructor(string expectedTitle, int expectedId, string title, int? id)
+        {
+            Recipe r = new Recipe(title, id);
+            Assert.NotNull(r.Title);
+            Assert.Equal(expectedId, r.Id);
+            Assert.Equal(expectedTitle, r.Title);
+        }
+    }
+}
diff --git a/MCTG/Tests/MCTGLib_UnitTests/Usings.cs b/MCTG/Tests/Model_UnitTests/Usings.cs
similarity index 100%
rename from MCTG/Tests/MCTGLib_UnitTests/Usings.cs
rename to MCTG/Tests/Model_UnitTests/Usings.cs