OpenSimulator is an open-source server platform originally launched in 2007 for hosting virtual worlds and metaverse environments.

In grid mode, various aspects of the simulation are separated among multiple processes, which can exist on different machines.

[4] During the OpenSimulator Community Conference 2018, the core developers announced they may not always seek to maintain compatibility with Linden Lab's Second Life Protocols, and may change or add facilities in line with differing aims.

These include virtual world content (OAR) and avatar inventory (IAR) save and load capabilities, extensions to the scripting language that enable saving and retrieval of text data to avatar inventory in notecard format and the creation and management of non-player characters (NPCs).

[citation needed] OpenSim also uses an architecture known as "Hypergrid", which allows users to teleport between multiple OpenSim-based virtual worlds by providing a hyperlinked map which indexes public grids.