1. SECOND LIFE: Created by Linden Labs. Linden Lab was founded in 1999 and is headquartered in San Francisco with additional offices in Seattle, Boston, Davis, and Charlottesville. This is a heavyweight in 3D VR Social World Environments.

  2. OSGRID: Created by Osgrid Inc, powered by the OpenSimulator project. The OpenSimulator project was founded in January 2007 by Darren Guard (also known as MW). It is a virtual world platform or virtual grid running the Open Simulator software based on Second Life protocols. It is a non-profit located in Georgia, North America.

  3. ENTROPIA UNIVERSE: Entropia Universe is a massively multiplayer online virtual universe designed by the software company MindArk, founded in 1999, based in Gothenburg, Sweden.

  4. UTHERVERSE: Utherverse, produced by Utherverse Inc. and later as Utherverse Digital Inc. It was founded in 2003 in Vancouver, Canada. It is primarily an Adult content focused company with one of its hypergrid metaverse locations being Red Light Center or RLC for short.

  5. VRChat: Developed by Graham Gaylor and Jesse Joudrey, based in San Francisco, California, North America. As their name suggested they are a Virtual Reality focused social simulator launched on Steam in February 2017. The developers defined the project by two aspects: its catalog of mini-games and its social capabilities.

  6. IMVU: IMVU was founded in 2004 and was originally backed by venture investors Menlo Ventures, AllegisCyber Capital, Bridgescale Partners, and Best Buy Capital. It lacks several aspects of most 3D virtual environments, being more of a toon style game combined with a chat feature. It does not have free movement features like either 3D, 2D or hybrid 3D and 2D games or point and click movement. Instead Movement is more static and changing position or location is instead done through selecting node triggers as spawn points.

  7. TWINITY: Twinity is another 3D online virtual world. It was initially developed by Metaversum GmbH. It was released in public beta version in September 2008. It was the first 3D online virtual world to incorporate true-to-scale replicas of large cities from all over the world. However, the company has recently begun to shift the focus away from a mirror world towards a more fantasy-oriented environment. All of the game's cities were removed in January 2012. On June 8, 2012 it also was acquired by ExitReality. It then began to include an option for avatar creation using Photofit.