diff --git a/src/main/java/duke/Duke.java b/src/main/java/duke/Duke.java
index b363084ab8..47b7019b09 100644
--- a/src/main/java/duke/Duke.java
+++ b/src/main/java/duke/Duke.java
@@ -2,11 +2,23 @@
 
 import java.io.IOException;
 
+import duke.exception.InvalidDataException;
+import duke.exception.InvalidTypeException;
+import duke.misc.Parser;
+import duke.misc.TaskList;
+
 public class Duke {
 
     private TaskList taskList;
     private Parser parser;
 
+    /**
+     * Constructor for Duke class
+     */
+    public Duke() {
+        taskList = new TaskList();
+    }
+
     /**
      * Function to get Duke's response to user inputs.
      *
@@ -27,11 +39,4 @@ public String getResponse(String input) {
         }
         return parser.allocate(input, taskList);
     }
-
-    /**
-     * Constructor for Duke class
-     */
-    public Duke() {
-        taskList = new TaskList();
-    }
 }
diff --git a/src/main/java/duke/DukeException.java b/src/main/java/duke/exception/DukeException.java
similarity index 92%
rename from src/main/java/duke/DukeException.java
rename to src/main/java/duke/exception/DukeException.java
index 6f4b58138f..95a7c0417b 100644
--- a/src/main/java/duke/DukeException.java
+++ b/src/main/java/duke/exception/DukeException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exception;
 
 /**
  * Exception class unique to Duke.
diff --git a/src/main/java/duke/InvalidDataException.java b/src/main/java/duke/exception/InvalidDataException.java
similarity index 92%
rename from src/main/java/duke/InvalidDataException.java
rename to src/main/java/duke/exception/InvalidDataException.java
index 5781b64bd9..bda91727e5 100644
--- a/src/main/java/duke/InvalidDataException.java
+++ b/src/main/java/duke/exception/InvalidDataException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exception;
 
 /**
  * Invalid Data Exception that extends Duke Exception class.
diff --git a/src/main/java/duke/InvalidDescriptionException.java b/src/main/java/duke/exception/InvalidDescriptionException.java
similarity index 93%
rename from src/main/java/duke/InvalidDescriptionException.java
rename to src/main/java/duke/exception/InvalidDescriptionException.java
index b6204e1ce9..0c177af2d1 100644
--- a/src/main/java/duke/InvalidDescriptionException.java
+++ b/src/main/java/duke/exception/InvalidDescriptionException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exception;
 
 /**
  * Invalid Description Exception that extends Duke Exception class.
diff --git a/src/main/java/duke/InvalidIndexException.java b/src/main/java/duke/exception/InvalidIndexException.java
similarity index 92%
rename from src/main/java/duke/InvalidIndexException.java
rename to src/main/java/duke/exception/InvalidIndexException.java
index ee411385ef..35efa5ebe4 100644
--- a/src/main/java/duke/InvalidIndexException.java
+++ b/src/main/java/duke/exception/InvalidIndexException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exception;
 
 /**
  * Invalid Index Exception that extends Duke Exception class.
diff --git a/src/main/java/duke/InvalidTypeException.java b/src/main/java/duke/exception/InvalidTypeException.java
similarity index 92%
rename from src/main/java/duke/InvalidTypeException.java
rename to src/main/java/duke/exception/InvalidTypeException.java
index 1219cc9ec9..791674d63b 100644
--- a/src/main/java/duke/InvalidTypeException.java
+++ b/src/main/java/duke/exception/InvalidTypeException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exception;
 
 /**
  * Invalid Type Exception that extends Duke Exception class.
diff --git a/src/main/java/duke/Parser.java b/src/main/java/duke/misc/Parser.java
similarity index 92%
rename from src/main/java/duke/Parser.java
rename to src/main/java/duke/misc/Parser.java
index 4c58cd63d3..5f259b5e1a 100644
--- a/src/main/java/duke/Parser.java
+++ b/src/main/java/duke/misc/Parser.java
@@ -1,7 +1,15 @@
-package duke;
+package duke.misc;
 
 import java.io.IOException;
 
+import duke.exception.InvalidDescriptionException;
+import duke.exception.InvalidIndexException;
+import duke.exception.InvalidTypeException;
+import duke.task.Deadline;
+import duke.task.Event;
+import duke.task.Task;
+import duke.task.Todo;
+
 /**
  * Parser class to handle user inputs.
  */
diff --git a/src/main/java/duke/Storage.java b/src/main/java/duke/misc/Storage.java
similarity index 94%
rename from src/main/java/duke/Storage.java
rename to src/main/java/duke/misc/Storage.java
index 8789185343..5e698d75b6 100644
--- a/src/main/java/duke/Storage.java
+++ b/src/main/java/duke/misc/Storage.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.misc;
 
 import java.io.BufferedReader;
 import java.io.FileReader;
@@ -10,6 +10,13 @@
 import java.nio.file.Paths;
 import java.util.ArrayList;
 
+import duke.exception.InvalidDataException;
+import duke.exception.InvalidTypeException;
+import duke.task.Deadline;
+import duke.task.Event;
+import duke.task.Task;
+import duke.task.Todo;
+
 /**
  * Storage class that interacts with the .txt file to store and retrieve data.
  */
diff --git a/src/main/java/duke/TaskList.java b/src/main/java/duke/misc/TaskList.java
similarity index 89%
rename from src/main/java/duke/TaskList.java
rename to src/main/java/duke/misc/TaskList.java
index d1fda62f01..2c3e817465 100644
--- a/src/main/java/duke/TaskList.java
+++ b/src/main/java/duke/misc/TaskList.java
@@ -1,8 +1,14 @@
-package duke;
+package duke.misc;
 
 import java.io.IOException;
 import java.util.ArrayList;
 
+import duke.exception.InvalidDataException;
+import duke.exception.InvalidDescriptionException;
+import duke.exception.InvalidIndexException;
+import duke.exception.InvalidTypeException;
+import duke.task.Task;
+
 /**
  * TaskList class to store all the tasks in Duke.
  */
@@ -18,15 +24,21 @@ public TaskList() {
         this.items = new ArrayList<>();
     }
 
+    /**
+     * Function to read in data from .txt file.
+     * @throws IOException In case data has errors
+     * @throws InvalidTypeException In cases data has an invalid type.
+     * @throws InvalidDataException In case data is invalid.
+     */
     public void initialise() throws IOException, InvalidTypeException, InvalidDataException {
         try {
             this.items = this.storage.readData();
-        } catch (IOException e) {
-            throw e;
         } catch (InvalidTypeException e) {
             throw e;
         } catch (InvalidDataException e) {
             throw e;
+        } catch (IOException e) {
+            throw e;
         }
     }
 
diff --git a/src/main/java/duke/Ui.java b/src/main/java/duke/misc/Ui.java
similarity index 82%
rename from src/main/java/duke/Ui.java
rename to src/main/java/duke/misc/Ui.java
index 9f1cc0906e..69766f003e 100644
--- a/src/main/java/duke/Ui.java
+++ b/src/main/java/duke/misc/Ui.java
@@ -1,15 +1,14 @@
-package duke;
+package duke.misc;
 
 /**
  * UI class to handle aesthetics of Duke.
  */
 public class Ui {
-    private static final String OPENING = " ____        _        \n"
+    static final String OPENING = " ____        _        \n"
             + "|  _ \\ _   _| | _____ \n"
             + "| | | | | | | |/ / _ \\\n"
             + "| |_| | |_| |   <  __/\n"
             + "|____/ \\__,_|_|\\_\\___|\n";
-
-    static final String WELCOME = OPENING + "\nHello I am Duke!\nWhat can I help you with?";
     static final String GOODBYE = "Goodbye. See you soon!";
+    static final String WELCOME = OPENING + "\nHello I am Duke!\nWhat can I help you with?";
 }
diff --git a/src/main/java/duke/DateTime.java b/src/main/java/duke/task/DateTime.java
similarity index 95%
rename from src/main/java/duke/DateTime.java
rename to src/main/java/duke/task/DateTime.java
index e3a8814f33..4901fdcb4c 100644
--- a/src/main/java/duke/DateTime.java
+++ b/src/main/java/duke/task/DateTime.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.task;
 
 import java.time.LocalDate;
 import java.time.format.DateTimeFormatter;
@@ -22,8 +22,6 @@ public class DateTime {
     public DateTime(String date) {
         if (isValidFormat(date)) {
             this.date = LocalDate.parse(date);
-        } else {
-            System.out.println(INVALID_DATE_MESSAGE);
         }
     }
 
diff --git a/src/main/java/duke/Deadline.java b/src/main/java/duke/task/Deadline.java
similarity index 88%
rename from src/main/java/duke/Deadline.java
rename to src/main/java/duke/task/Deadline.java
index c420fce488..8e7af19826 100644
--- a/src/main/java/duke/Deadline.java
+++ b/src/main/java/duke/task/Deadline.java
@@ -1,10 +1,10 @@
-package duke;
+package duke.task;
 
 /**
  * Deadline class for tasks that have a set deadline.
  */
 public class Deadline extends Task {
-    static final String symbol = "D";
+    static final String SYMBOL = "D";
     private DateTime deadline;
 
     /**
@@ -38,7 +38,7 @@ public Deadline(String title, boolean isComplete, String deadline) {
     @Override
     public String saveString() {
         int completeSymbol = this.complete ? 1 : 0;
-        return String.format("%s|%d|%s|%s", symbol, completeSymbol, this.title, this.deadline.saveString());
+        return String.format("%s|%d|%s|%s", SYMBOL, completeSymbol, this.title, this.deadline.saveString());
     }
 
     /**
@@ -49,6 +49,6 @@ public String saveString() {
     @Override
     public String toString() {
         String completeSymbol = this.complete ? "[/]" : "[X]";
-        return String.format("[%s]%s %s (by: %s)", symbol, completeSymbol, this.title, this.deadline);
+        return String.format("[%s]%s %s (by: %s)", SYMBOL, completeSymbol, this.title, this.deadline);
     }
 }
diff --git a/src/main/java/duke/Event.java b/src/main/java/duke/task/Event.java
similarity index 87%
rename from src/main/java/duke/Event.java
rename to src/main/java/duke/task/Event.java
index 8b37757da3..36f2e8f9aa 100644
--- a/src/main/java/duke/Event.java
+++ b/src/main/java/duke/task/Event.java
@@ -1,10 +1,10 @@
-package duke;
+package duke.task;
 
 /**
  * Event class for tasks that have a set timing.
  */
 public class Event extends Task {
-    static final String symbol = "E";
+    static final String SYMBOL = "E";
     private DateTime time;
 
     /**
@@ -38,7 +38,7 @@ public Event(String title, boolean isComplete, String time) {
     @Override
     public String saveString() {
         int completeSymbol = this.complete ? 1 : 0;
-        return String.format("%s|%d|%s|%s", symbol, completeSymbol, this.title, this.time.saveString());
+        return String.format("%s|%d|%s|%s", SYMBOL, completeSymbol, this.title, this.time.saveString());
     }
 
     /**
@@ -49,6 +49,6 @@ public String saveString() {
     @Override
     public String toString() {
         String completeSymbol = this.complete ? "[/]" : "[X]";
-        return String.format("[%s]%s %s (at: %s)", symbol, completeSymbol, this.title, this.time);
+        return String.format("[%s]%s %s (at: %s)", SYMBOL, completeSymbol, this.title, this.time);
     }
 }
diff --git a/src/main/java/duke/Task.java b/src/main/java/duke/task/Task.java
similarity index 87%
rename from src/main/java/duke/Task.java
rename to src/main/java/duke/task/Task.java
index 9527a0d6af..fb5ebd0dfa 100644
--- a/src/main/java/duke/Task.java
+++ b/src/main/java/duke/task/Task.java
@@ -1,10 +1,10 @@
-package duke;
+package duke.task;
 
 /**
  * Task class to represent a task to be manipulated by Duke.
  */
 public class Task {
-    static final String symbol = "T";
+    static final String SYMBOL = "T";
     protected String title;
     protected boolean complete;
 
@@ -43,7 +43,7 @@ public void complete() {
      */
     public String saveString() {
         int completeSymbol = this.complete ? 1 : 0;
-        return String.format("%s|%d|%s", symbol, completeSymbol, this.title);
+        return String.format("%s|%d|%s", SYMBOL, completeSymbol, this.title);
     }
 
     /**
@@ -54,6 +54,6 @@ public String saveString() {
     @Override
     public String toString() {
         String completeSymbol = this.complete ? "[/]" : "[X]";
-        return String.format("[%s]%s %s", symbol, completeSymbol, this.title);
+        return String.format("[%s]%s %s", SYMBOL, completeSymbol, this.title);
     }
 }
diff --git a/src/main/java/duke/Todo.java b/src/main/java/duke/task/Todo.java
similarity index 96%
rename from src/main/java/duke/Todo.java
rename to src/main/java/duke/task/Todo.java
index 1be7a1c47a..b9e0bc4925 100644
--- a/src/main/java/duke/Todo.java
+++ b/src/main/java/duke/task/Todo.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.task;
 
 /**
  * Todo class for Tasks that need to be completed.
diff --git a/src/test/java/duke/DukeTest.java b/src/test/java/duke/DukeTest.java
deleted file mode 100644
index b6ba1b14d9..0000000000
--- a/src/test/java/duke/DukeTest.java
+++ /dev/null
@@ -1,48 +0,0 @@
-package duke;
-
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
-import org.junit.jupiter.api.Test;
-
-public class DukeTest {
-
-    private TaskList t = new TaskList();
-
-    private Storage s = new Storage();
-
-    @Test
-    public void invalidCommandTest() {
-        try {
-            Parser.handleInput("example hello");
-        } catch (InvalidTypeException e) {
-            assertEquals("OOPS!!! I'm sorry, but I don't know what that means :-(",
-                    e.getMessage());
-        } catch (InvalidDescriptionException e) {
-            assertEquals("OOPS!!! The description of a task cannot be empty",
-                    e.getMessage());
-        }
-    }
-
-    @Test
-    public void invalidIndexTest() {
-        try {
-            t.completeTask(-1);
-        } catch (InvalidIndexException e) {
-            assertEquals("OOPS!!! The index you have chosen is out of bounds",
-                    e.getMessage());
-        }
-    }
-
-    @Test
-    public void invalidDataTest() {
-        try {
-            s.stringToTask("example hello");
-        } catch (InvalidTypeException e) {
-            assertEquals("OOPS!!! I'm sorry, but I don't know what that means :-(",
-                    e.getMessage());
-        } catch (InvalidDataException e) {
-            assertEquals("OOPS!!! The data here is invalid!",
-                    e.getMessage());
-        }
-    }
-}
diff --git a/src/test/java/duke/misc/ParserTest.java b/src/test/java/duke/misc/ParserTest.java
new file mode 100644
index 0000000000..5b589ec14d
--- /dev/null
+++ b/src/test/java/duke/misc/ParserTest.java
@@ -0,0 +1,23 @@
+package duke.misc;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+import duke.exception.InvalidDescriptionException;
+import duke.exception.InvalidTypeException;
+
+public class ParserTest {
+    @Test
+    public void invalidCommandTest() {
+        try {
+            Parser.handleInput("example hello");
+        } catch (InvalidTypeException e) {
+            assertEquals("OOPS!!! I'm sorry, but I don't know what that means :-(",
+                    e.getMessage());
+        } catch (InvalidDescriptionException e) {
+            assertEquals("OOPS!!! The description of a task cannot be empty",
+                    e.getMessage());
+        }
+    }
+}
diff --git a/src/test/java/duke/misc/StorageTest.java b/src/test/java/duke/misc/StorageTest.java
new file mode 100644
index 0000000000..672ce2ba71
--- /dev/null
+++ b/src/test/java/duke/misc/StorageTest.java
@@ -0,0 +1,25 @@
+package duke.misc;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+import duke.exception.InvalidDataException;
+import duke.exception.InvalidTypeException;
+
+public class StorageTest {
+    private Storage s = new Storage();
+
+    @Test
+    public void invalidDataTest() {
+        try {
+            s.stringToTask("example hello");
+        } catch (InvalidTypeException e) {
+            assertEquals("OOPS!!! I'm sorry, but I don't know what that means :-(",
+                    e.getMessage());
+        } catch (InvalidDataException e) {
+            assertEquals("OOPS!!! The data here is invalid!",
+                    e.getMessage());
+        }
+    }
+}
diff --git a/src/test/java/duke/misc/TaskListTest.java b/src/test/java/duke/misc/TaskListTest.java
new file mode 100644
index 0000000000..091b320a7c
--- /dev/null
+++ b/src/test/java/duke/misc/TaskListTest.java
@@ -0,0 +1,21 @@
+package duke.misc;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+import duke.exception.InvalidIndexException;
+
+public class TaskListTest {
+    private TaskList t = new TaskList();
+
+    @Test
+    public void invalidIndexTest() {
+        try {
+            t.completeTask(-1);
+        } catch (InvalidIndexException e) {
+            assertEquals("OOPS!!! The index you have chosen is out of bounds",
+                    e.getMessage());
+        }
+    }
+}