A Virtual Military Organization (VMO) is a dedicated hobby organization that uses simulation to model the operations of a military. Virtual Military Organizations (VMOs) generally have a presence on the internet, similar to real military organizations. Most VMOs simulate military operations to varying degrees. A newer variant of Virtual Military is the MilSim unit. MilSim units differ from Virtual Military by placing emphasis on the simulation of military tactics in their chosen gaming platform, whereas traditionally, VMOs have placed emphasis on simulating the bigger picture, including a full military career path, logistics systems, coordinated movement of equipment around the world, and prolonged military operations. Although VMOs may appear to be a type of gaming clan, a key difference is that a gaming clan's primary purpose is to be an "organized group of players that regularly play together." VMOs are essentially role-playing environments within which an individual can immerse themselves. Realism groups are semantically similar; however, their primary focus is usually on following real-life procedures as much as possible. Therefore, tactical realism and MilSim are almost synonymous in the gaming world. A Google search for 'Virtual Military' reveals quite a few VMOs that go to varying degrees of depth to pursue their goal.
Each VMO has their own mission. Some VMOs will simulate an individual military unit, others an entire branch of the military, and yet others attempt to simulate Joint Operations with multiple branches. Most VMOs offer a rank system that provides a career path within the organization. VMOs will often offer a variety of training, in order to allow new members to familiarize themselves with the organization's doctrine.
Each VMO chooses to either follow an immersive style, a realistic style, or a combination of both. Immersion as it relates to this topic is the pursuit of a feeling of complete saturation in a military operation, whereas realism is the rigid following of real world rules, tactics, and customs of a real-life counterpart. For some people, realism is in fact immersive, so there is an element of crossover between the two terms. While most VMOs will incorporate a rank structure, some extend that to incorporate features such as Military Logistics systems,economics models, awards and medals, and custom debriefing reports.