Unity is a cross-platform game engine developed by Unity Technologies, first announced and released in June 2005 at Apple Inc.'s Worldwide Developers Conference as a Mac OS X-exclusive game engine. As of 2018, the engine had been extended to support more than 25 platforms. The engine can be used to create three-dimensional, two-dimensional, virtual reality, and augmented reality games, as well as simulations and other experiences. The engine has been adopted by industries outside video gaming, such as film, automotive, architecture, engineering and construction.
The Unreal Engine is a game engine developed by Epic Games, first showcased in the 1998 first-person shooter game Unreal. Although initially developed for first-person shooters, it has been used in a variety of other genres, including platformers, fighting games, MMORPGs, and other RPGs. Written in C++, the Unreal Engine features a high degree of portability, supporting a wide range of platforms.
CryEngine (officially stylized as CRYENGINE) is a game engine designed by the German game developer Crytek. It has been used in all of their titles with the initial version being used in Far Cry, and continues to be updated to support new consoles and hardware for their games. It has also been used for many third-party games under Crytek's licensing scheme, including Sniper: Ghost Warrior 2 and SNOW. Warhorse Studios uses a modified version of the engine for their medieval RPG Kingdom Come: Deliverance. Ubisoft maintains an in-house, heavily modified version of CryEngine from the original Far Cry called the Dunia Engine, which is used in their later iterations of the Far Cry series.