diff --git a/app/src/main/java/com/example/ca_contest/CountrySelectorActivity.kt b/app/src/main/java/com/example/ca_contest/CountrySelectorActivity.kt
index 231228d..60f12fc 100644
--- a/app/src/main/java/com/example/ca_contest/CountrySelectorActivity.kt
+++ b/app/src/main/java/com/example/ca_contest/CountrySelectorActivity.kt
@@ -23,9 +23,12 @@ import retrofit2.Callback
 import retrofit2.Response
 import kotlin.collections.ArrayList
 
-
 class CountrySelectorActivity : AppCompatActivity() {
 
+    companion object {
+        const val PROGRESS_BAR_TITLE = "Récupération des pays..."
+    }
+
     private var data: ArrayList<Country> = ArrayList()
 
     override fun onCreate(savedInstanceState: Bundle?) {
@@ -35,7 +38,7 @@ class CountrySelectorActivity : AppCompatActivity() {
 
         // Progress Bar
         val progressDialog = ProgressDialog(this)
-        progressDialog.setTitle("Récupération des pays...")
+        progressDialog.setTitle(PROGRESS_BAR_TITLE)
         progressDialog.setCancelable(false)
         progressDialog.show()
 
diff --git a/app/src/main/java/com/example/ca_contest/MainActivity.kt b/app/src/main/java/com/example/ca_contest/MainActivity.kt
index 20aa4b6..170a624 100644
--- a/app/src/main/java/com/example/ca_contest/MainActivity.kt
+++ b/app/src/main/java/com/example/ca_contest/MainActivity.kt
@@ -12,20 +12,20 @@ import com.example.ca_contest.dao.AppDatabaseHelper
 import java.util.*
 
 class MainActivity : AppCompatActivity() {
-    private lateinit var countryAdapter: HomepageCountryAdapter
-    //    private lateinit var imageView: ImageView
     override fun onCreate(savedInstanceState: Bundle?)
     {
         super.onCreate(savedInstanceState)
 
         setContentView(R.layout.activity_main)
 
+        // Initialize RecyclerView
         val recycler = findViewById<RecyclerView>(R.id.list_country)
         recycler.setHasFixedSize(true)
 
         val layoutManager = LinearLayoutManager(this)
         recycler.layoutManager = layoutManager
 
+        // Fetch Items in Database
         val adapter = HomepageCountryAdapter(
             AppDatabaseHelper
                 .getDatabase(this)
diff --git a/app/src/main/java/com/example/ca_contest/adapters/CountryAdapter.kt b/app/src/main/java/com/example/ca_contest/adapters/CountryAdapter.kt
index 1c3d458..d9ca0a9 100644
--- a/app/src/main/java/com/example/ca_contest/adapters/CountryAdapter.kt
+++ b/app/src/main/java/com/example/ca_contest/adapters/CountryAdapter.kt
@@ -11,6 +11,7 @@ import androidx.recyclerview.widget.RecyclerView
 import com.example.ca_contest.api.Country
 import com.squareup.picasso.Picasso
 
+// Adapter for the CountrySelector
 class CountryAdapter(list: ArrayList<Country>) : RecyclerView.Adapter<CountryAdapter.CountryViewHolder>() {
 
     private var list: ArrayList<Country> = ArrayList()
diff --git a/app/src/main/java/com/example/ca_contest/adapters/HomepageCountryAdapter.kt b/app/src/main/java/com/example/ca_contest/adapters/HomepageCountryAdapter.kt
index ab6fcc5..a13663a 100644
--- a/app/src/main/java/com/example/ca_contest/adapters/HomepageCountryAdapter.kt
+++ b/app/src/main/java/com/example/ca_contest/adapters/HomepageCountryAdapter.kt
@@ -11,6 +11,7 @@ import androidx.recyclerview.widget.RecyclerView
 import com.example.ca_contest.dao.Country
 import com.squareup.picasso.Picasso
 
+// Adapter for the homepage
 class HomepageCountryAdapter(list: List<Country>) : RecyclerView.Adapter<HomepageCountryAdapter.CountryViewHolder>() {
 
     private var list: List<Country> = ArrayList()
diff --git a/app/src/main/java/com/example/ca_contest/api/ApiClient.kt b/app/src/main/java/com/example/ca_contest/api/ApiClient.kt
index 3351896..91b6edc 100644
--- a/app/src/main/java/com/example/ca_contest/api/ApiClient.kt
+++ b/app/src/main/java/com/example/ca_contest/api/ApiClient.kt
@@ -6,6 +6,7 @@ import okhttp3.logging.HttpLoggingInterceptor
 import retrofit2.Retrofit
 import retrofit2.converter.gson.GsonConverterFactory
 
+// API Client
 object ApiClient {
 
     var BASE_URL:String="https://restcountries.eu/"
diff --git a/app/src/main/java/com/example/ca_contest/api/ApiInterface.kt b/app/src/main/java/com/example/ca_contest/api/ApiInterface.kt
index 752acb1..00a46cb 100644
--- a/app/src/main/java/com/example/ca_contest/api/ApiInterface.kt
+++ b/app/src/main/java/com/example/ca_contest/api/ApiInterface.kt
@@ -3,6 +3,7 @@ package com.example.ca_contest.api
 import retrofit2.Call
 import retrofit2.http.GET
 
+// functions to get the differents elements
 interface ApiInterface {
 
     @GET("rest/v2/all")
diff --git a/app/src/main/java/com/example/ca_contest/api/Country.kt b/app/src/main/java/com/example/ca_contest/api/Country.kt
index 5e27dc0..aec25f1 100644
--- a/app/src/main/java/com/example/ca_contest/api/Country.kt
+++ b/app/src/main/java/com/example/ca_contest/api/Country.kt
@@ -3,6 +3,7 @@ package com.example.ca_contest.api
 import com.google.gson.annotations.Expose
 import com.google.gson.annotations.SerializedName
 
+// Model for The API
 data class Country(
     @Expose
     @SerializedName("name")
diff --git a/app/src/main/java/com/example/ca_contest/dao/AppDatabase.kt b/app/src/main/java/com/example/ca_contest/dao/AppDatabase.kt
index a43fc21..4ad4520 100644
--- a/app/src/main/java/com/example/ca_contest/dao/AppDatabase.kt
+++ b/app/src/main/java/com/example/ca_contest/dao/AppDatabase.kt
@@ -5,6 +5,7 @@ import androidx.room.Database
 import androidx.room.RoomDatabase
 import androidx.room.TypeConverters
 
+// Database Manager
 @Database(entities = [Country::class], version = 1)
 @TypeConverters(Converters::class)
 abstract class AppDatabase : RoomDatabase()
diff --git a/app/src/main/java/com/example/ca_contest/dao/AppDatabaseHelper.kt b/app/src/main/java/com/example/ca_contest/dao/AppDatabaseHelper.kt
index 475bc4b..8ec635d 100644
--- a/app/src/main/java/com/example/ca_contest/dao/AppDatabaseHelper.kt
+++ b/app/src/main/java/com/example/ca_contest/dao/AppDatabaseHelper.kt
@@ -3,6 +3,7 @@ package com.example.ca_contest.dao
 import android.content.Context
 import androidx.room.Room
 
+// Helper for the Database System
 class AppDatabaseHelper(context: Context)
 {
     // Bloc de code "static" :
diff --git a/app/src/main/java/com/example/ca_contest/dao/Country.kt b/app/src/main/java/com/example/ca_contest/dao/Country.kt
index 237fd7c..db29b06 100644
--- a/app/src/main/java/com/example/ca_contest/dao/Country.kt
+++ b/app/src/main/java/com/example/ca_contest/dao/Country.kt
@@ -4,6 +4,7 @@ import androidx.room.Entity
 import androidx.room.PrimaryKey
 import java.util.Date
 
+// Model for the country
 @Entity(tableName = "country")
 class Country(
     @PrimaryKey(autoGenerate = true)
diff --git a/app/src/main/java/com/example/ca_contest/dao/CountryDAO.kt b/app/src/main/java/com/example/ca_contest/dao/CountryDAO.kt
index c7c7a1b..32ecd38 100644
--- a/app/src/main/java/com/example/ca_contest/dao/CountryDAO.kt
+++ b/app/src/main/java/com/example/ca_contest/dao/CountryDAO.kt
@@ -2,9 +2,10 @@ package com.example.ca_contest.dao
 
 import androidx.room.*
 
+// DAO for the Country
 @Dao
 abstract class CountryDAO {
-    @Query("SELECT * FROM country")
+    @Query("SELECT * FROM country ORDER BY date ASC")
     abstract fun getListCountry(): List<Country>
     @Insert
     abstract fun insert(vararg country: Country)
diff --git a/app/src/main/java/com/example/ca_contest/libs/Converters.kt b/app/src/main/java/com/example/ca_contest/libs/Converters.kt
index 7db5b69..6eeb346 100644
--- a/app/src/main/java/com/example/ca_contest/libs/Converters.kt
+++ b/app/src/main/java/com/example/ca_contest/libs/Converters.kt
@@ -3,6 +3,7 @@ package com.example.ca_contest.libs
 import androidx.room.TypeConverter
 import java.util.*
 
+// Convert from and to a Java Date Object to a SQL Date
 class Converters {
     @TypeConverter
     fun fromTimestamp(value: Long?): Date? {