diff --git a/src/TodoList.php b/src/TodoList.php
new file mode 100644
index 0000000..c17252f
--- /dev/null
+++ b/src/TodoList.php
@@ -0,0 +1,64 @@
+<?php
+
+namespace MMK2410\MyTodoList;
+
+use InvalidArgumentException;
+
+class TodoList
+{
+    const ExceptionMsgTodoNotFound = "Could not find todo with given ID";
+
+    private string $name;
+    private array $todos;
+    private int $id;
+
+    public function __construct(string $name)
+    {
+        $this->id = IdManager::generateID(self::class);
+        $this->name = $name;
+        $this->todos = array();
+    }
+
+    public function getID(): int {
+        return $this->id;
+    }
+
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    public function setName(string $name)
+    {
+        $this->name = $name;
+    }
+
+    public function addTodo(Todo $todo): void
+    {
+        $this->todos[] = $todo;
+    }
+
+    public function getTodos(): array
+    {
+        return $this->todos;
+    }
+
+    public function getTodoById(int $id): ?Todo
+    {
+        foreach ($this->todos as $todo) {
+            if ($todo->getID() == $id) {
+                return $todo;
+            }
+        }
+        throw new InvalidArgumentException(self::ExceptionMsgTodoNotFound);
+    }
+
+    public function deleteTodoById(int $id): void
+    {
+        foreach ($this->todos as $key => $todo) {
+            if ($todo->getID() == $id) {
+                unset($this->todos[$key]);
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/tests/TodoListTest.php b/tests/TodoListTest.php
new file mode 100644
index 0000000..5142191
--- /dev/null
+++ b/tests/TodoListTest.php
@@ -0,0 +1,117 @@
+<?php declare(strict_types=1);
+
+use MMK2410\MyTodoList\Todo;
+use MMK2410\MyTodoList\TodoList;
+use PHPUnit\Framework\TestCase;
+
+class TodoListTest extends TestCase
+{
+    public function testCreateTodoList(): void {
+        $todolist1 = new TodoList("My Todo List");
+        $todolist2 = new TodoList("My Todo List");
+        $this->assertNotEquals(
+            $todolist1->getID(),
+            $todolist2->getID(),
+            "Expected todo lists to have different UIDs but they have the same."
+        );
+    }
+
+    public function testTodoListHasName(): void
+    {
+        $name = "My Todo List";
+        $todolist = new TodoList($name);
+        $this->assertEquals(
+            $name,
+            $todolist->getName(),
+            "Created todo list with name '$name', but it has name '{$todolist->getName()}'",
+        );
+    }
+
+    public function testChangeTodoListName(): void
+    {
+        $todolist = new TodoList("Old name");
+        $new_todolist_name = "New name";
+        $todolist->setName($new_todolist_name);
+        $this->assertEquals(
+            $new_todolist_name,
+            $todolist->getName(),
+            "Renamed todo list to '$new_todolist_name', but its name is '{$todolist->getName()}'"
+        );
+    }
+
+    public function testGetEmptyTodos(): void
+    {
+        $todolist = new TodoList("Some list");
+        $todoAmount = sizeof($todolist->getTodos());
+        $this->assertEquals(
+            0,
+            $todoAmount,
+            "Got wrong amount of todos. Expected 0, got $todoAmount"
+        );
+    }
+
+    public function testGetTodos(): void
+    {
+        $todolist = new TodoList("Some list");
+        for ($i = 1; $i < 3; $i++) {
+            $todolist->addTodo(new Todo("Some todo"));
+        }
+        $i--; // Decrement $i for using it in the assertion
+        $todoAmount = sizeof($todolist->getTodos());
+        $this->assertEquals(
+            $i,
+            $todoAmount,
+            "Got wrong amount of todos. Expected $i, got $todoAmount"
+        );
+    }
+
+    public function testAddTodo(): void
+    {
+        $todolist = new TodoList("Some list");
+        $todo = new Todo("Some todo");
+        $todolist->addTodo($todo);
+        $id_todo = $todo->getID();
+        $id_todo_from_list = $todolist->getTodos()[0]->getID();
+        $this->assertEquals(
+            $id_todo,
+            $id_todo_from_list,
+            "Got wrong todo. Expected ID $id_todo, got $id_todo_from_list"
+        );
+    }
+
+    public function testGetTodoById(): void
+    {
+        $todolist = new TodoList("Some list");
+        $todo = new Todo("Some todo");
+        $todolist->addTodo($todo);
+        $id_todo = $todo->getID();
+        $id_todo_from_list = $todolist->getTodoById($id_todo)->getID();
+        $this->assertEquals(
+            $id_todo,
+            $id_todo_from_list,
+            "Got wrong todo. Expected ID $id_todo, got $id_todo_from_list"
+        );
+    }
+
+    public function testGetNonExistentTodoById(): void
+    {
+        $todolist = new TodoList("Some list");
+        $this->expectException(InvalidArgumentException::class);
+        $this->expectExceptionMessage(TodoList::ExceptionMsgTodoNotFound);
+        $todolist->getTodoById(-1);
+    }
+
+    public function testDeleteTodoById(): void
+    {
+        $todolist = new TodoList("Some list");
+        $todo = new Todo("Delete me");
+        $todolist->addTodo($todo);
+        $todolist->deleteTodoById($todo->getID());
+        $amountTodos = sizeof($todolist->getTodos());
+        $this->assertEquals(
+            0,
+            $amountTodos,
+            "Expected not todos to be left, but there are/is $amountTodos left"
+        );
+    }
+}