diff --git a/src/UE23_270525_Chatserver/ChatClient.java b/src/UE23_270525_Chatserver/ChatClient.java
new file mode 100644
index 0000000..ac765ee
--- /dev/null
+++ b/src/UE23_270525_Chatserver/ChatClient.java
@@ -0,0 +1,130 @@
+package UE23_270525_Chatserver;
+
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
+import java.net.Socket;
+
+public class ChatClient extends Thread {
+    Socket client;
+    String name = "";
+
+    public ChatClient(Socket s) {
+        client = s;
+    }
+
+    @Override
+    public void run() {
+        try (BufferedReader br = new BufferedReader(new InputStreamReader(client.getInputStream())); BufferedWriter wr = new BufferedWriter(new OutputStreamWriter(client.getOutputStream()))) {
+            while (true) {
+                wr.write("Willkommen beim Mathe-Quiz\n\rWie heftig hättest du es gerne?");
+                wr.flush();
+                while (true) {
+                    int level;
+                    wr.write("\n\rBitte gibt eine Zahl zwischen 1 und 3 ein. (Leer für 1): ");
+                    wr.flush();
+                    try {
+                        String input = br.readLine();
+                        if (input == null || input.trim().isEmpty()) break;
+                        level = Integer.parseInt(input);
+                    } catch (Exception _) {
+                        continue;
+                    }
+                    if (level < 1 || level > 3) continue;
+                    this.level = level;
+                    break;
+                }
+                while (true) {
+                    int anz;
+                    wr.write("\n\rWie viele Fragen meochtest du loesen (1 - 999) (Leer für 10): ");
+                    wr.flush();
+                    try {
+                        String input = br.readLine();
+                        if (input == null || input.trim().isEmpty()) break;
+                        anz = Integer.parseInt(input);
+                    } catch (Exception _) {
+                        continue;
+                    }
+                    if (anz < 1 || anz > 999) continue;
+                    this.anzCals = anz;
+                    break;
+                }
+                for (int i = 1; i <= anzCals; i++) {
+                    int type = randomInRange(1, 4), solution, a, b;
+                    String operator;
+                    switch (level) {
+                        case 1 -> {
+                            a = randomInRange(1, 10);
+                            b = randomInRange(1, 10);
+                        }
+                        case 2 -> {
+                            a = randomInRange(-100, 100);
+                            b = randomInRange(-100, 100);
+                        }
+                        case 3 -> {
+                            a = randomInRange(-10_000, 10_000);
+                            b = randomInRange(-10_000, 10_000);
+                        }
+                        default -> throw new IllegalStateException("Unexpected value: " + level);
+                    }
+                    switch (type) {
+                        case 1 -> {
+                            operator = "+";
+                            solution = a + b;
+                        }
+                        case 2 -> {
+                            operator = "-";
+                            solution = a - b;
+                        }
+                        case 3 -> {
+                            operator = "*";
+                            solution = a * b;
+                        }
+                        case 4 -> {
+                            operator = "/";
+                            solution = a / (b == 0 ? 1 : b);
+                        }
+                        default -> throw new IllegalStateException("Unexpected value: " + type);
+                    }
+                    String question = "(Level " + level + ") Frage " + i + ": " + a + " " + operator + " " + b + " = ";
+                    wr.write(question);
+                    wr.flush();
+                    while (true) {
+                        String message = "\n\rFalsch :( .. versuche es noch einmal\n\n\r" + question;
+                        try {
+                            String input = br.readLine();
+                            if (input == null || input.trim().isEmpty() || Integer.parseInt(input) != solution) {
+                                wr.write(message);
+                                wr.flush();
+                                continue;
+                            }
+                        } catch (Exception _) {
+                            wr.write(message);
+                            wr.flush();
+                            continue;
+                        }
+                        wr.write("\n\rrichtig :)\n\n\r");
+                        wr.flush();
+                        break;
+                    }
+                }
+                wr.write("\n\n\n\rHerzlichen Glückwunsch du hast es geschafft!!\n");
+                wr.flush();
+                boolean end = true;
+                while (true) {
+                    wr.write("\n\rMoechtest du noch einmal spielen? [y/N]: ");
+                    wr.flush();
+                    String input = br.readLine();
+                    if (input == null || input.trim().isEmpty() || input.trim().equalsIgnoreCase("n")) break;
+                    if (input.trim().equalsIgnoreCase("y")) {
+                        end = false;
+                        break;
+                    }
+                }
+                if (end) break;
+            }
+        } catch (Exception _) {
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/UE23_270525_Chatserver/ChatServer.java b/src/UE23_270525_Chatserver/ChatServer.java
new file mode 100644
index 0000000..c9a8936
--- /dev/null
+++ b/src/UE23_270525_Chatserver/ChatServer.java
@@ -0,0 +1,18 @@
+package UE23_270525_Chatserver;
+
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.Socket;
+
+public class ChatServer {
+    public static void main(String[] args) {
+        try (ServerSocket server = new ServerSocket(1000)) {
+            while (true) {
+                System.out.println("Ready to connect");
+                Socket client = server.accept();
+                new ChatClient(client).start();
+            }
+        } catch (IOException _) {
+        }
+    }
+}
diff --git a/src/UE23_270525_Chatserver/SEW3 UE23 2024 Chatserver.pdf b/src/UE23_270525_Chatserver/SEW3 UE23 2024 Chatserver.pdf
new file mode 100644
index 0000000..b3fd9ab
Binary files /dev/null and b/src/UE23_270525_Chatserver/SEW3 UE23 2024 Chatserver.pdf differ