diff --git a/not-alone-server/src/main/java/fr/univnantes/alma/model/player/Creature.java b/not-alone-server/src/main/java/fr/univnantes/alma/model/player/Creature.java
new file mode 100644
index 0000000000000000000000000000000000000000..2d4bb7278161b9c14570db8cf64d3291a5d7e64d
--- /dev/null
+++ b/not-alone-server/src/main/java/fr/univnantes/alma/model/player/Creature.java
@@ -0,0 +1,7 @@
+package fr.univnantes.alma.model.player;
+
+/**
+ * Single Creature game player.
+ */
+public class Creature extends Player{
+}
diff --git a/not-alone-server/src/main/java/fr/univnantes/alma/model/player/Player.java b/not-alone-server/src/main/java/fr/univnantes/alma/model/player/Player.java
new file mode 100644
index 0000000000000000000000000000000000000000..e96035f449e07b0e231203afa7c2587011cb1ccc
--- /dev/null
+++ b/not-alone-server/src/main/java/fr/univnantes/alma/model/player/Player.java
@@ -0,0 +1,7 @@
+package fr.univnantes.alma.model.player;
+
+/**
+ * Single game player.
+ */
+public abstract class Player {
+}
diff --git a/not-alone-server/src/main/java/fr/univnantes/alma/model/player/Tracked.java b/not-alone-server/src/main/java/fr/univnantes/alma/model/player/Tracked.java
new file mode 100644
index 0000000000000000000000000000000000000000..7d4ee7415c0b619d81cb5944ceeb62eae2c5d28c
--- /dev/null
+++ b/not-alone-server/src/main/java/fr/univnantes/alma/model/player/Tracked.java
@@ -0,0 +1,7 @@
+package fr.univnantes.alma.model.player;
+
+/**
+ * Single Tracked game player.
+ */
+public class Tracked extends Player{
+}
diff --git a/not-alone-server/src/main/java/fr/univnantes/alma/model/square/Square.java b/not-alone-server/src/main/java/fr/univnantes/alma/model/square/Square.java
new file mode 100644
index 0000000000000000000000000000000000000000..ad71c7ffeffdd9a667007969c4d544d08ca010ba
--- /dev/null
+++ b/not-alone-server/src/main/java/fr/univnantes/alma/model/square/Square.java
@@ -0,0 +1,28 @@
+package fr.univnantes.alma.model.square;
+
+/***
+ * Game board square.
+ */
+public abstract class Square {
+
+    /**
+     * Square position.
+     */
+    private int position;
+
+    /**
+     * Create new instance of Square.
+     * @param position square position
+     */
+    public Square(int position) {
+        this.position = position;
+    }
+
+    /**
+     * Return the position of the square.
+     * @return position of the square
+     */
+    public int getPosition() {
+        return position;
+    }
+}
diff --git a/not-alone-server/src/main/java/fr/univnantes/alma/model/square/TrackedSquare.java b/not-alone-server/src/main/java/fr/univnantes/alma/model/square/TrackedSquare.java
new file mode 100644
index 0000000000000000000000000000000000000000..e56b7a84288bb0e07fe359654d03a6917be635dc
--- /dev/null
+++ b/not-alone-server/src/main/java/fr/univnantes/alma/model/square/TrackedSquare.java
@@ -0,0 +1,13 @@
+package fr.univnantes.alma.model.square;
+
+public class TrackedSquare extends Square{
+
+    /**
+     * Create new instance of Square.
+     *
+     * @param position square position
+     */
+    public TrackedSquare(int position) {
+        super(position);
+    }
+}