Virtual reality (VR) is a computer-simulated environment, whether that environment is a simulation of the real world or an imaginary world
The term "artificial reality", coined by Myron Krueger, has been in use since the 1970s.
The concept of virtual reality was popularized in mass media by movies such as Brainstorm.
The seven different concepts of Virtual Reality: simulation, interaction, artificiality, immersion, telepresence, full-body immersion, and network communication.

Immersion is the state of consciousness where an immersant's awareness of physical self is diminished or lost by being surrounded in an engrossing total environment; often artificial.

This mental state is frequently accompanied by spatial excess, intense focus, a distorted sense of time, and effortless action.,

An effective VR experience causes you to become unaware of your real surroundings and focus on your existence inside the virtual environment.

Two main components of immersion are:

Depth of information
Depth of information refers to the amount and quality of data in the signals a user receives when interacting in a virtual environment

Breadth of information.
Breadth of information as the “number of sensory dimensions simultaneously presented”.