diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/Ghost.java b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/Ghost.java
new file mode 100644
index 0000000..9e5fc16
--- /dev/null
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/Ghost.java
@@ -0,0 +1,9 @@
+package ch.unibas.dmi.dbis.cs108.Klassenstruktur;
+
+public class Ghost extends Passenger {
+    protected boolean isOG;             //true if the Ghost is the original ghost.
+
+    public boolean getIsOG() {
+        return isOG;
+    }
+}
diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/GhostNPC.java b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/GhostNPC.java
new file mode 100644
index 0000000..7d80968
--- /dev/null
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/GhostNPC.java
@@ -0,0 +1,22 @@
+package ch.unibas.dmi.dbis.cs108.Klassenstruktur;
+
+public class GhostNPC extends Ghost{
+
+    /**
+     * Creates a new GhostNPC. Should be used at game start or if a HumanNPC is turned into a ghost.
+     * @param position position on the train
+     * @param name player name. if null, then a default name is used.
+     * @param isOG true if the ghost is the original ghost.
+     */
+    public GhostNPC(int position, String name, boolean isOG) {
+        this.isOG = isOG;
+        this.position = position;
+        this.sock = null;
+        isGhost = true;
+        isPlayer = false;
+        kickedOff = false;
+        if (name == null) {
+            this.name = "Robot Nr. " + position;
+        } else this.name = name;
+    }
+}
diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/GhostPlayer.java b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/GhostPlayer.java
new file mode 100644
index 0000000..3ee1b9c
--- /dev/null
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/GhostPlayer.java
@@ -0,0 +1,29 @@
+package ch.unibas.dmi.dbis.cs108.Klassenstruktur;
+
+import java.net.Socket;
+
+public class GhostPlayer extends Ghost{
+
+    /**
+     * Creates a new GhostPlayer. Should be used at game start or if a HumanPlayer is turned into a ghost.
+     * @param position position on the train
+     * @param name name. if null, then a default name is used.
+     * @param sock the socket for the player.
+     * @param isOG true if the ghost is the original ghost.
+     */
+    public GhostPlayer(int position, String name, Socket sock, boolean isOG) {
+        this.position = position;
+        this.sock = sock;
+        this.isOG = isOG;
+        isGhost = true;
+        isPlayer = true;
+        kickedOff = false;
+        if (name == null) {
+            this.name = "Human Nr. " + position;
+        } else this.name = name;
+    }
+
+    public void send(String msg) {
+        //todo: pass message along to client.
+    }
+}
diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/Human.java b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/Human.java
new file mode 100644
index 0000000..eeda085
--- /dev/null
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/Human.java
@@ -0,0 +1,4 @@
+package ch.unibas.dmi.dbis.cs108.Klassenstruktur;
+
+public class Human extends Passenger {
+}
diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/HumanNPC.java b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/HumanNPC.java
new file mode 100644
index 0000000..87c47cd
--- /dev/null
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/HumanNPC.java
@@ -0,0 +1,5 @@
+package ch.unibas.dmi.dbis.cs108.Klassenstruktur;
+
+public class HumanNPC extends Human {
+
+}
diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/HumanPlayer.java b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/HumanPlayer.java
new file mode 100644
index 0000000..f968ac9
--- /dev/null
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/HumanPlayer.java
@@ -0,0 +1,4 @@
+package ch.unibas.dmi.dbis.cs108.Klassenstruktur;
+
+public class HumanPlayer extends Human{
+}
diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/Passenger.java b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/Passenger.java
new file mode 100644
index 0000000..e53eccf
--- /dev/null
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/Klassenstruktur/Passenger.java
@@ -0,0 +1,58 @@
+package ch.unibas.dmi.dbis.cs108.Klassenstruktur;
+
+import java.net.Socket;
+
+public class Passenger {
+    protected int position;               //the player's Cabin number (1 to 6)
+    protected String name;                //the player's Name
+    protected Boolean isGhost;            //boolean regarding if the player is a ghost. Could probably be removed since ghost is a subclass but I'm keeping it in.
+    protected Boolean isPlayer;           //same here
+    protected Boolean kickedOff;          //true if the player has been voted off.
+    protected Socket sock;                //the socket for the client associated with this Passenger, for NPCs, this can be null.
+    //todo: maybe this should be a thread or some class instead of a socket? depends on client-server structure...
+
+
+    /**
+     * Sends a protocol message to the respective player.
+     * @param msg the message that is sent to this player.
+    **/
+    public void send(String msg) {
+        //todo: send protocol message to the respective client OR process messages for NPCS
+    }
+
+    /**
+     * sets the name of this passenger.
+     * @param name the new name for this passenger.
+     */
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    /**
+     * sets the kickedOff status of this Passenger
+     * @param kickedOff should be set to true if the passenger has been kicked off.
+     */
+    public void setKickedOff(boolean kickedOff) {
+        this.kickedOff = kickedOff;
+    }
+
+    public int getPosition() {
+        return position;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public Boolean getIsGhost() {
+        return isGhost;
+    }
+
+    public Boolean getKickedOff() {
+        return kickedOff;
+    }
+
+    public Boolean getIsPlayer() {
+        return isPlayer;
+    }
+}