Virtual Reality is defined as "the computer-generated simulation of a three-dimensional image or environment that can be interacted with in a seemingly real or physical way by a person using special electronic equipment, such as a helmet with a screen inside or gloves fitted with sensors" (Oxford Languages). This technology can be used for entertainment purpose and for more serious purpose such as medicine or education.

What are the three types of VR?

The VR simulations can be grouped into three categories: non-immersive, semi-immersive and fully-immersive.

1. Non-Immersive Virtual Reality Simulation

In the non-immersive VR simulation, you can interact with the environment while being fully aware that you are into a simulation. An example of a non-immersive experience is when you play a 3D video game and you can control your character. These type of experiences are not new to the user because in the past decade, there have been other similar technologies that allowed the user to interact with the virtual space, such as Wii Sports.

Another example is watching an animated movie on your VR headset. You will be able to look around while knowing you are in a simulation and none of it is real.

2. Semi-Immersive Virtual Reality Simulation

In the semi-immersive VR simulation, you can experience a more immersive environment, while still being aware that you are in a simulation. Most of your experiences will be visual. The semi-immersive simulation can be used for educational and training purpose. For example, doctors can experience the surgery procedure in VR or pilots can experience flying planes before having the experience in real life. They will have the feeling that they are in a different reality and the visual experience will feel closer to reality than just watching a video.

3. Fully-Immersive Virtual Reality Simulation 

In the fully-immersive VR simulation, you will feel as if you are entirely in a different reality. The user can wear headphones, gloves and even suspension gear. This type of simulation is ideal for entertainment, because it gives the full experience: visual, auditory and sensorial. This type of simulation has been mainly used for gaming, where the user could move around and become one with his virtual character.

Another example is watching a horror movie on your VR headset. You will be able to move around, to look around, follow the characters while listening to all the sounds on the headset.

Conclusion

To sum up, there are multiple applications for each of the 3 categories of Virtual Reality. One of the categories that interest me most is filmmaking. There are not many content creators for VR and there is a huge opportunity for those who are starting now compared to those who will start creating VR movies when it will become popular.

I did not know there are multiple types of virtual reality. Now that I have read your post, I understand it better.