Characteristics of Unity is

☛ It is a multi-platform game engine with features like ( 3D objects, physics, animation, scripting, lighting etc.)

☛ Accompanying script editor

☛ MonoDevelop (win/mac)

☛ It can also use Visual Studio (Windows)

☛ 3D terrain editor

☛ 3D object animation manager

☛ GUI System

☛ Many platforms executable exporter Web player/ Android/Native application/Wii

☛ In Unity 3D, you can assemble art and assets into scenes and environments like adding special effects, physics and animation, lighting, etc.