SecondLife

Second Life is an online virtual world, developed by Linden Lab, launched on June 23, 2003. A number of free client programs, or Viewers are used to use the Second Life world so that the users in Second Life, called Residents, can interact with each other through avatars. Residents can explore the world, meet other residents, socialize, participate in individual and group activities, and create and trade virtual property and services with one another. Second Life is intended for people aged 16 and over, with the exception of 13–15-year-old users restricted to the Second Life region of a sponsoring institution (e.g. school).

Built into the software, SecondLife is a three-dimensional modeling tool based on simple geometric shapes that allows residents to build virtual objects. There is also a procedural scripting language, Linden Scripting Language, which can be used to add interactivity to objects. Sculpted prims (sculpties), mesh, textures for clothing or other objects, animations, and gestures can be created using external software and imported. The Second Life terms of service provide that users retain copyright for any content they create, and the server and client provide simple digital rights management (DRM) functions. However, Linden Lab changed their terms of service in August 2013, to be able to use user-generated content for any purpose. The new terms of service prevents users from using textures from 3rd-party texture services, as some of them pointed out explicitly. Users can also photograph in Second Life with the camera technology the client programs have.

OpenSim

OpenSimulator is an open-source multi-platform, multi-user 3D application server. It can be used to create and environment and through some of its facility it allows users to visit other OpenSimulator installations across the web.

OpenSimulator allows virtual world developers to personalise their worlds using the technologies they feel work best - we've designed the framework to be easily extensible. OpenSimulator is written in C#, running both on Windows over the .NET Framework and on Unix-like machines over the Mono framework. The source code is released under a BSD License, a commercially friendly license to embed OpenSimulator in products.

Out of the box, OpenSimulator can be used to simulate virtual environments similar to Second Life™, given that it supports the core of SL's messaging protocol. Therefore these virtual worlds can be accessed with the regular SL viewers. However, OpenSimulator does not want to become a clone of the Second Life server platform. In fact, the project pursues innovative feature development with an aspiration towards becoming the bare bones, but extensible, server of the 3D Web.

Minecraft
 

Minecraft is a sandbox indie game originally created by Swedish programmer Markus "Notch" Persson and later developed and published by Mojang. Its full release version was launched on November 18, 2011.

The game is available on nearly every platform like Personal Computers (Windows PC, Mac OS, Linux), consoles (Xbox360, Xbox Live Arcade, Xbox One*, PS3, Playstation Network PSN and PS4*) and mobile devices (e.g. Android, iOS, PS Vita*) as retail version or digital download. *=scheduled for a release in August

All versions of Minecraft receive periodic updates.

The creative and building aspects of Minecraft allow players to build constructions out of textured cubes in a 3D procedurally generated world. These cubes represent materials with different physical properties. Other activities in the game include exploration, gathering resources, crafting, and combat. Gameplay in its commercial release has four principal modes:

Survival Mode

In this mode players have to gather natural resources (such as wood, stone, etc.) found in the environment in order to craft certain blocks and items.

Creative mode

In creative mode, players have access to most of the resources and items in the game through the inventory menu, and can place or remove them instantly. Players, able to fly freely around the game world, do not take environmental or mob damage, and are not affected by hunger. The game mode helps players focus on building and creating large projects.

Adventure mode

Adventure mode was added to Minecraft in version 1.3; it was designed specifically so that players could experience user crafted custom maps and adventures. Gameplay is similar to survival mode but introduces various player restrictions such as disabling the ability to place and destroy blocks without the appropriate tools.

Multiplayer

Multiplayer on Minecraft is available through player-hosted servers and enables multiple players to interact and communicate with each other on a single world. Players can run their own servers or use a hosting provider. Single player worlds have local area network support, allowing players to join worlds on locally interconnected computers without a server setup.

Since the game is still in development even post-release important features are added with each update. Due to the feedback of many players the community developed a server version called “bukkit” that is highly customizable to suit the player’s needs and interests. This version enables the installation of additional plugins to modify the game e.g. changing the game’s rule set. Based on the customizability of Minecraft new gameplay scenarios are created e.g. Galacticraft2 or ComputerCraft. The bukkit-server version of Minecraft enables the use of specific, efficient world building tools like WorldEdit, which can be very important for the application in the pedagogical context otherwise every structure would have to be built cube by cube.

Applications

The possible applications of Minecraft have been discussed extensively, especially in the fields of computer-aided design and education, e.g. the possibility of using the game to redesign public buildings and parks, stating that rendering using Minecraft was much more user-friendly for the community, making it easier to envision the functionality of new buildings and parks. Various software has been developed to allow virtual designs to be printed using professional 3D printers or personal printers such as MakerBot andRepRap.

The project Block By Block, a cooperation between UN Habitat and Mojang, allows young people who live in specific real-world environments to participate in designing the changes they would like to see. Using Minecraft, the community has helped reconstruct the areas of concern, and citizens are invited to enter the Minecraftservers and modify their own neighborhood.

Minecraft in Education

Minecraft has also been used in educational settings. In 2011, an international group of educators and programmers formed the organization TeacherGaming with the goal of introducing Minecraft into schools. They offer a special customized version of Minecraft, called MinecraftEdu, which is specifically designed for the use in the classroom.
A wide variety of educational activities involving the game have been developed to teach students various subjects, including history, language arts and science. For an example, teacher Eric Walker from Kuwait built a Minecraft world consisting of a historical theme park for students to learn about and explore ancient civilizations and geography.

^{Minecraft conference}

MineCon is an official Minecraft convention held annually.

Reference

OpenSim website; Linden Lab website; Wikipedia - SecondLife; Minecraft:  http://en.wikipedia.org/wiki/Minecraft