diff --git a/Behavioral/State/OrderContext.php b/Behavioral/State/ContextOrder.php
similarity index 52%
rename from Behavioral/State/OrderContext.php
rename to Behavioral/State/ContextOrder.php
index c18961c..3b64440 100644
--- a/Behavioral/State/OrderContext.php
+++ b/Behavioral/State/ContextOrder.php
@@ -4,29 +4,29 @@ declare(strict_types=1);
 
 namespace DesignPatterns\Behavioral\State;
 
-class OrderContext
+class ContextOrder
 {
-    private State $state;
+    private StateOrder $state;
 
-    public static function create(): OrderContext
+    public static function create(): ContextOrder
     {
         $order = new self();
-        $order->state = new StateCreated();
+        $order->state = new CreateOrder();
 
         return $order;
     }
 
-    public function setState(State $state)
+    public function setState(StateOrder $state): void
     {
         $this->state = $state;
     }
 
-    public function proceedToNext()
+    public function proceedToNext(): void
     {
         $this->state->proceedToNext($this);
     }
 
-    public function toString()
+    public function toString(): string
     {
         return $this->state->toString();
     }
diff --git a/Behavioral/State/StateCreated.php b/Behavioral/State/CreateOrder.php
similarity index 52%
rename from Behavioral/State/StateCreated.php
rename to Behavioral/State/CreateOrder.php
index 22c184a..1385871 100644
--- a/Behavioral/State/StateCreated.php
+++ b/Behavioral/State/CreateOrder.php
@@ -4,11 +4,11 @@ declare(strict_types=1);
 
 namespace DesignPatterns\Behavioral\State;
 
-class StateCreated implements State
+class CreateOrder implements StateOrder
 {
-    public function proceedToNext(OrderContext $context)
+    public function proceedToNext(ContextOrder $context): void
     {
-        $context->setState(new StateShipped());
+        $context->setState(new ShippingOrder());
     }
 
     public function toString(): string
diff --git a/Behavioral/State/StateDone.php b/Behavioral/State/OrderDone.php
similarity index 67%
rename from Behavioral/State/StateDone.php
rename to Behavioral/State/OrderDone.php
index 6ee3fde..5f1a3f7 100644
--- a/Behavioral/State/StateDone.php
+++ b/Behavioral/State/OrderDone.php
@@ -4,9 +4,9 @@ declare(strict_types=1);
 
 namespace DesignPatterns\Behavioral\State;
 
-class StateDone implements State
+class OrderDone implements StateOrder
 {
-    public function proceedToNext(OrderContext $context)
+    public function proceedToNext(ContextOrder $context): void
     {
         // there is nothing more to do
     }
diff --git a/Behavioral/State/README.rst b/Behavioral/State/README.rst
index fb78606..6934b45 100644
--- a/Behavioral/State/README.rst
+++ b/Behavioral/State/README.rst
@@ -20,33 +20,33 @@ Code
 
 You can also find this code on `GitHub`_
 
-OrderContext.php
+ContextOrder.php
 
-.. literalinclude:: OrderContext.php
+.. literalinclude:: ContextOrder.php
    :language: php
    :linenos:
 
-State.php
+StateOrder.php
 
-.. literalinclude:: State.php
+.. literalinclude:: StateOrder.php
    :language: php
    :linenos:
 
-StateCreated.php
+CreateOrder.php
 
-.. literalinclude:: StateCreated.php
+.. literalinclude:: CreateOrder.php
    :language: php
    :linenos:
 
-StateShipped.php
+ShippingOrder.php
 
-.. literalinclude:: StateShipped.php
+.. literalinclude:: ShippingOrder.php
    :language: php
    :linenos:
 
-StateDone.php
+OrderDone.php
 
-.. literalinclude:: StateDone.php
+.. literalinclude:: OrderDone.php
    :language: php
    :linenos:
 
diff --git a/Behavioral/State/StateShipped.php b/Behavioral/State/ShippingOrder.php
similarity index 53%
rename from Behavioral/State/StateShipped.php
rename to Behavioral/State/ShippingOrder.php
index d883413..d82591d 100644
--- a/Behavioral/State/StateShipped.php
+++ b/Behavioral/State/ShippingOrder.php
@@ -4,11 +4,11 @@ declare(strict_types=1);
 
 namespace DesignPatterns\Behavioral\State;
 
-class StateShipped implements State
+class ShippingOrder implements StateOrder
 {
-    public function proceedToNext(OrderContext $context)
+    public function proceedToNext(ContextOrder $context): void
     {
-        $context->setState(new StateDone());
+        $context->setState(new OrderDone());
     }
 
     public function toString(): string
diff --git a/Behavioral/State/State.php b/Behavioral/State/StateOrder.php
similarity index 58%
rename from Behavioral/State/State.php
rename to Behavioral/State/StateOrder.php
index ed88495..1847158 100644
--- a/Behavioral/State/State.php
+++ b/Behavioral/State/StateOrder.php
@@ -4,9 +4,9 @@ declare(strict_types=1);
 
 namespace DesignPatterns\Behavioral\State;
 
-interface State
+interface StateOrder
 {
-    public function proceedToNext(OrderContext $context);
+    public function proceedToNext(ContextOrder $context): void;
 
     public function toString(): string;
 }
diff --git a/Behavioral/State/Tests/StateTest.php b/Behavioral/State/Tests/StateTest.php
index 721efee..2b668e2 100644
--- a/Behavioral/State/Tests/StateTest.php
+++ b/Behavioral/State/Tests/StateTest.php
@@ -4,38 +4,38 @@ declare(strict_types=1);
 
 namespace DesignPatterns\Behavioral\State\Tests;
 
-use DesignPatterns\Behavioral\State\OrderContext;
+use DesignPatterns\Behavioral\State\ContextOrder;
 use PHPUnit\Framework\TestCase;
 
 class StateTest extends TestCase
 {
-    public function testIsCreatedWithStateCreated()
+    public function testIsCreatedWithStateCreated(): void
     {
-        $orderContext = OrderContext::create();
+        $orderContext = ContextOrder::create();
 
         $this->assertSame('created', $orderContext->toString());
     }
 
-    public function testCanProceedToStateShipped()
+    public function testCanProceedToStateShipped(): void
     {
-        $contextOrder = OrderContext::create();
+        $contextOrder = ContextOrder::create();
         $contextOrder->proceedToNext();
 
         $this->assertSame('shipped', $contextOrder->toString());
     }
 
-    public function testCanProceedToStateDone()
+    public function testCanProceedToStateDone(): void
     {
-        $contextOrder = OrderContext::create();
+        $contextOrder = ContextOrder::create();
         $contextOrder->proceedToNext();
         $contextOrder->proceedToNext();
 
         $this->assertSame('done', $contextOrder->toString());
     }
 
-    public function testStateDoneIsTheLastPossibleState()
+    public function testStateDoneIsTheLastPossibleState(): void
     {
-        $contextOrder = OrderContext::create();
+        $contextOrder = ContextOrder::create();
         $contextOrder->proceedToNext();
         $contextOrder->proceedToNext();
         $contextOrder->proceedToNext();