Multi-User Domain Object Oriented


Multi-User Domain Object Oriented (MOO) is a type of online virtual environment where multiple users can connect, interact, and create content collaboratively. It combines object-oriented programming principles with text-based communication, enabling users to create custom objects and environments. MOOs were popular in the 1990s and served as a precursor to modern Massively Multiplayer Online Games (MMOGs) and virtual worlds.

Key Takeaways

  1. Multi-User Domain Object Oriented (MOO) is a type of virtual environment where multiple users can interact, collaborate, and create objects in a shared, object-oriented space.
  2. MOOs are often used for educational, social, and entertainment purposes, providing real-time communication and immersive experiences for users.
  3. MOOs can be customized and expanded by users with programming skills, typically using the MOO programming language, allowing for the creation of interactive objects, virtual environments, and advanced functionality.


The technology term “Multi-User Domain Object Oriented” (MOO) is important because it refers to a class of internet-based, multi-user virtual environments where users can collaboratively create, manipulate, and interact with objects in a shared space.

The object-oriented nature of MOOs provides users with a highly customizable environment, allowing for the design of complex settings and scenarios such as games, learning environments, and social spaces.

This technology has had a significant impact on the landscape of online interaction and communication, as well as in education and training, by promoting user engagement, collaborative problem-solving, and interactive storytelling.

MOOs have served as precursors to modern virtual reality and massively multiplayer online games, showcasing the potential for immersive and dynamic user experiences in the digital world.


Multi-User Domain Object Oriented (MU* or MOO) is a technology that holds great importance in the realm of computer-mediated communication, collaborative learning, and online gaming. At its core, a MOO is an environment where multiple users connect and interact with each other in real-time using text-based representations within a virtual world. These virtual worlds are typically expansive and rich, allowing users to navigate through rooms and spaces, engage with in-world objects, and communicate with other participants.

MOOs can be molded to cater to a diverse range of purposes, including elaborate multiplayer games, educational platforms, and professional collaboration spaces. The versatility of the MOO platform makes it all the more intriguing and valuable in harnessing the power of virtual worlds for various goals. One of the notable aspects of a MOO is how it embraces the object-oriented programming (OOP) paradigm, enabling easy extensibility and customization of the virtual world.

This empowers users to not only engage with the environment but also contribute to its ongoing development by creating new objects, offering unique functionalities, and altering the world’s structure. In educational settings, MOOs have served as a valuable tool to facilitate project-based learning and stimulate creative thinking as students build and explore the virtual world together. Similarly, in professional settings, a MOO encourages meaningful, interactive communication among peers, enabling simultaneous chatting and data exchange.

By providing an immersive and adaptive environment, Multi-User Domain Object Oriented technology fosters creativity, collaboration, and communication across various domains.

Examples of Multi-User Domain Object Oriented

Multi-User Domain Object Oriented (MOO) is a text-based virtual reality system in which users can interact with each other and create virtual environments. It combines features from Multi-User Dungeons (MUDs) and object-oriented programming. Here are three real-world examples of MOO technology in use:

LambdaMOO: LambdaMOO was one of the most famous MOOs and served as an early example of an online community that used MOO technology. Launched in 1990, LambdaMOO allowed users to connect, interact, and create virtual spaces to socialize, discuss, and collaborate on various subjects. LambdaMOO was known for its rich social dynamics and was often used for research into online communities and social interactions.

Diversity University MOO (DU MOO): Established in 1993, Diversity University MOO was an educational platform that used MOO technology to create a virtual learning environment. Teachers and students from around the world could interact with each other, attend virtual classes, share resources, and collaborate on projects. Diversity University MOO was one of the first attempts to use this technology for distance learning and showcased the potential of MOOs in achieving educational goals.

BioMOO: BioMOO is a specialized MOO that was created for the global community of biologists, providing them with a virtual space to interact and share information on scientific research. Launched in 1993 by Jaime Prilusky, BioMOO facilitated global collaboration among researchers, hosted seminars and conferences, and even included virtual laboratories for performing experiments. This platform allowed scientists from around the world to communicate and collaborate on biotechnology research and provided a unique way to exchange knowledge in a virtual space.

FAQ: Multi-User Domain Object Oriented (MOO)

1. What is a Multi-User Domain Object Oriented (MOO)?

A Multi-User Domain Object Oriented (MOO) is a text-based online virtual reality system in which multiple users can connect, interact, create objects, and communicate with each other. It is an extension of the Multi-User Dungeon (MUD) concept, incorporating object-oriented programming concepts to allow for greater flexibility and customization.

2. How does MOO differ from MUD?

While both MOO and MUD are text-based virtual environments, MOO incorporates object-oriented programming principles, providing users with an advanced level of customization and allowing them to create, modify or delete objects. MUDs generally use a set of predefined objects and rules, with limited possibilities for user-generated content.

3. How do you connect to a MOO?

To connect to a MOO, you will need a specialized client program or a Telnet client that supports the Telnet protocol. You can find various MOO clients on the internet, some specifically designed for certain MOOs. Once you have a client installed, connect to the MOO’s address and port number as provided on its website or documentation.

4. Is programming knowledge required to use a MOO?

Basic interaction in a MOO does not require programming knowledge, as it mostly involves typing commands similar to a text-based adventure game. However, to take full advantage of MOO’s object-oriented capabilities and create custom objects or interactions, some programming knowledge of MOO’s scripting language is helpful.

5. Can I create my own MOO?

Yes, you can create your own MOO by downloading a MOO server software package, configuring it on your computer or server, and setting up the initial virtual environment. You will need some technical skills to set up the server, as well as knowledge of the internet protocols and the MOO programming language to customize it according to your preferences.

Related Technology Terms

  • Virtual Worlds
  • Text-Based Online Environments
  • Interactive Fiction
  • Online Communities
  • Object-Oriented Programming

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