docs: first draft of README.

README.md

@@ -1,2 +1,37 @@
 # Puzzler-VR
-A VR Puzzle Game for Cardboard Using Unity 
+A VR Puzzle Game for Cardboard Using Unity.
+
+## Gameplay Video
+Gameplay from the start to the end.
+
+[![Alt text](https://img.youtube.com/vi/fXgvAwGKskg/0.jpg)](https://www.youtube.com/watch?v=fXgvAwGKskg "Click to play on youtube.com")
+
+## Software
+* **Game Engine :**
+  * [Unity 3D](https://unity3d.com/).
+* **Packages :**
+  * [Google VR SDK for Unity](https://developers.google.com/vr/unity/).
+  * [Unity Standard Assets](https://www.assetstore.unity3d.com/en/#!/content/32351).
+  * [iTween](https://www.assetstore.unity3d.com/en/#!/content/84).
+  * [Sky5X One](https://www.assetstore.unity3d.com/en/#!/content/6332).
+
+## Target Platform
+The main target platform is android mobiles to use it with cardboard viewer.
+
+## Scripts
+Most of the scripts were provided by _Udacity_. I have edited them to match my needs.
+
+## Art
+most of the models and textures are provided by _Udacity starter files_. I used some images for texturing the particles.
+
+## sounds
+I used some of _Udacity_ provided sounds and I downloaded some free sounds from the internet.
+
+## Particle Systems
+I used fire particle system from standard assets and customized it.
+
+## Notes
+This Project was required for Udacity _**VR Software Development Course**_ in [VR developer Nanodegree](https://www.udacity.com/course/vr-developer-nanodegree--nd017).
+
+## License
+This project is licensed under the MIT License - see the [LICENSE.md](LICENSE.md) file for details