Update README with architecture summary

Author: untoldengine

README.md

@@ -133,6 +133,29 @@ setEntityKinetics(entityId: player) // Enable Physics System
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+# Untold Engine Architecture — Summary  
+
+Untold Engine is built on a **data-oriented Entity–Component–System (ECS)** architecture designed for clarity, performance, and extensibility.  
+
+- **Entities**  
+  Entities are lightweight IDs. They have no behavior or state on their own.  
+
+- **Components**  
+  Components are plain data containers attached to entities. They describe an entity’s properties or capabilities (e.g., `Transform`, `Mesh`, `Light`, `Dribbling`).  
+  - Components are the **primary way to add new behavior** in Untold Engine.  
+  - All components are serializable and editor-friendly, so they can be saved, loaded, and modified at runtime.  
+
+- **Systems**  
+  Systems are stateless functions that run each frame. They query entities with specific components, read and update their data, and drive the simulation.  
+  - Example: a **DribblingSystem** looks for entities with a `DribblingComponent`, updates their animations and movement based on input, and interacts with the ball.  
+
+- **Editor Integration**  
+  Because components are declarative and Codable, they are automatically exposed to the Editor. Developers and designers can attach/remove components, tweak fields in the Inspector, and see changes take effect instantly when switching to Play Mode.  
+
+This separation of entities, components, and systems keeps the codebase modular, testable, and cache-friendly. New features are added by creating **a new component (data) + a system (logic)**, without modifying the engine core.  
+
+---
+
 ## Using the Untold Engine
 
 The Untold Engine is powered by modular systems that simplify game development. Click on the links to get started.