diff --git a/src/main/java/Duke.java b/src/main/java/Duke.java
index 5d313334c..93e160441 100644
--- a/src/main/java/Duke.java
+++ b/src/main/java/Duke.java
@@ -1,3 +1,5 @@
+import java.util.Scanner;
+
 public class Duke {
     public static void main(String[] args) {
         String logo = " ____        _        \n"
@@ -6,5 +8,129 @@ public static void main(String[] args) {
                 + "| |_| | |_| |   <  __/\n"
                 + "|____/ \\__,_|_|\\_\\___|\n";
         System.out.println("Hello from\n" + logo);
+        System.out.println("Hello! I'm Duke");
+        System.out.println("What can I do for you?");
+
+        Scanner scanner = new Scanner(System.in);
+        Task[] tasks = new Task[100];
+        int taskCount = 0;
+        String input;
+
+        while (true) {
+            input = scanner.nextLine();
+            if (input.equals("bye")) {
+                System.out.println("Bye. Hope to see you again soon!");
+                break;
+            } else if (input.equals("list")) {
+                System.out.println("Here are the tasks in your list:");
+                for (int i = 0; i < taskCount; i++) {
+                    System.out.println((i + 1) + "." + tasks[i]);
+                }
+            } else if (input.startsWith("mark ")) {
+                int taskIndex = Integer.parseInt(input.split(" ")[1]) - 1;
+                tasks[taskIndex].markAsDone();
+                System.out.println("Nice! I've marked this task as done:");
+                System.out.println("  " + tasks[taskIndex]);
+            } else if (input.startsWith("unmark ")) {
+                int taskIndex = Integer.parseInt(input.split(" ")[1]) - 1;
+                tasks[taskIndex].markAsNotDone();
+                System.out.println("OK, I've marked this task as not done yet:");
+                System.out.println("  " + tasks[taskIndex]);
+            } else if (input.startsWith("todo ")) {
+                String description = input.substring(5);
+                tasks[taskCount] = new ToDo(description);
+                taskCount++;
+                System.out.println("Got it. I've added this task:");
+                System.out.println("  " + tasks[taskCount - 1]);
+                System.out.println("Now you have " + taskCount + " tasks in the list.");
+            } else if (input.startsWith("deadline ")) {
+                String[] parts = input.substring(9).split(" /by ");
+                tasks[taskCount] = new Deadline(parts[0], parts[1]);
+                taskCount++;
+                System.out.println("Got it. I've added this task:");
+                System.out.println("  " + tasks[taskCount - 1]);
+                System.out.println("Now you have " + taskCount + " tasks in the list.");
+            } else if (input.startsWith("event ")) {
+                String[] parts = input.substring(6).split(" /from | /to ");
+                tasks[taskCount] = new Event(parts[0], parts[1], parts[2]);
+                taskCount++;
+                System.out.println("Got it. I've added this task:");
+                System.out.println("  " + tasks[taskCount - 1]);
+                System.out.println("Now you have " + taskCount + " tasks in the list.");
+            } else {
+                System.out.println("I'm sorry, I don't understand that command.");
+            }
+        }
+
+        scanner.close();
+    }
+}
+
+class Task {
+    protected String description;
+    protected boolean isDone;
+
+    public Task(String description) {
+        this.description = description;
+        this.isDone = false;
+    }
+
+    public void markAsDone() {
+        this.isDone = true;
+    }
+
+    public void markAsNotDone() {
+        this.isDone = false;
+    }
+
+    public String getStatusIcon() {
+        return (isDone ? "X" : " ");
+    }
+
+    @Override
+    public String toString() {
+        return "[" + getStatusIcon() + "] " + description;
+    }
+}
+
+class ToDo extends Task {
+
+    public ToDo(String description) {
+        super(description);
+    }
+
+    @Override
+    public String toString() {
+        return "[T]" + super.toString();
+    }
+}
+
+class Deadline extends Task {
+    protected String by;
+
+    public Deadline(String description, String by) {
+        super(description);
+        this.by = by;
+    }
+
+    @Override
+    public String toString() {
+        return "[D]" + super.toString() + " (by: " + by + ")";
+    }
+}
+
+class Event extends Task {
+    protected String from;
+    protected String to;
+
+    public Event(String description, String from, String to) {
+        super(description);
+        this.from = from;
+        this.to = to;
+    }
+
+    @Override
+    public String toString() {
+        return "[E]" + super.toString() + " (from: " + from + " to: " + to + ")";
     }
 }