Virtual Reality (VR) is an interactive, computer generated environment that one can enter and interact with. Augmented Reality (AR) is a live direct or indirect view of a physical, real-world environment whose elements are augmented by computer-generated sensory input such as sound, video, graphics or GPS data.
The two terms have become more popular in the past few years as they have grown more mainstream. While many people confuse the two concepts to be synonymous due to their similar names and uses in industry, AR differs from VR because it does not fully immerse you into another world like VR does. Instead AR enhances your current surroundings with different features overlaid on top of them which creates a whole new experience for you every time you use it.
Virtual Reality is a type of technology that makes people feel as if they’re inside whatever world someone has created, from realistic environments such as video games and movies to being able to interact with virtual objects in real time; this is accomplished by using headsets which will come together with either wires (tethered) or wirelessly (mobile).
AR is a live direct or indirect view of a physical, real-world environment whose elements are augmented by computer generated sensory input such as sound, video graphics or GPS data and which is accessed through a device with an advanced display system such as a head mounted display (HMD).
A recent example of AR is a Pokémon Go game where people can capture virtual creatures and interact with their surroundings in real time using an app on their phone. The iPhone’s camera tracks the location, orientation, and movement to match the images shown on screen as you travel around your town or city collecting different types of digital critters.
Common VR and AR Terms
- 180° Video: A video that is filmed horizontally with a view of 180 degrees.
- 360° Video: A type of immersive media where the viewer can look in any direction and see what’s happening at all times around them, as if they’re on the scene. 360 degree videos are spherical images captured by cameras with an omnidirectional lens or multiple lenses to capture all the angles.
- Ambisonics: A surround sound technique that captures sounds from every direction around listeners to create the sensation of being immersed inside them. It’s considered more natural compared to stereophonic techniques (think stereo speakers). The first ambisonic recordings were made by NASA during space missions at Houston’s Manned Spacecraft Center in 1967 using Ampex Model 200 tape recorders.
- Aspect Ratio: Size relationship between width and height of images in cinema screens and video frames.
- Cardboard: Cardboard was developed by the company that owns what many people describe as Earth’s most popular search engine. The project’s goal is to make virtual reality accessible for everyone and not just those who can afford it. This effort led to the development of Google Cardboard—a low cost VR headset made from cardboard that you fold yourself before inserting your smartphone into one side in order to use apps on the other. If you want to try out VR, the first thing you need is a Google Cardboard headset and an Android phone with its screen size between four inches (or older iPhones) and six inches.
- Degrees of Freedom: The number or types of ways in which movement can occur within a digital environment, often three-dimensional space but sometimes two dimensional as well. These are typically measured by degrees—such as 360° rotation around one’s vertical axis). Degrees that measure rotational movements include yaw, pitch, and roll; those measuring translational movements include locomotion forwards/backwards/leftward/rightward/upwards/downwards.
- Dollhouse view: The camera is positioned on the ceiling looking down at a scene from above, creating an effect of photographing miniature dolls in their living room or house. The viewer’s perspective may be so low that people appear like life-size dolls if they are not tall enough to reach it; alternatively, the user can fly up to any height and see things as giants would when viewing from such a position (as seen in video games).
- Equirectangular Projection: A type of map projection used for mapping spherical surfaces onto flat surfaces such as maps where the parallels and meridians have been flattened into straight lines.
- Eye tracking: An emerging technology which measures eye movement and uses it as a means of input. The user wears an eye tracker, which may be mounted on glasses like Google Glass or integrated into the display device in front of one’s eyes.
- FOV Field of View: Measures how much you can see out your virtual reality headset at any given time (e.g., 90°).
- Frame Rate: The frequency with which video frames are displayed for either television or cinema systems per second; the higher this number is, the smoother motions will appear to viewers watching content that was filmed with the same frame rate (e.g., 30fps opposed to 24 fps).
- Gaze-based interaction: A type of human interface where physical controls have been replaced by gaze-tracking software.
- Haptics: A form of human-machine interaction involving the sense of touch, typically those which involve applying forces or vibrations to a user. A haptic glove is one tool that provides tactile feedback; some video games use rumble packs and other vibrating controllers for this purpose as well.
- Head mounted display HMD: Head mounted displays are devices with electronic screens — most often OLEDS or LCDs – built into them that allow users to look at computer generated images in front of their eyes while they wear it (e.g., Google Glass). They have stereoscopic lenses so people can see three-dimensional virtual environments like VR headsets do but may not be able to provide positional tracking features such as head position changes relative to the environment.
- Head tracking: Technology used to calculate a user’s head movements, often accomplished with sensors on the HMD of a VR headset or controller in the hand. As your virtual reality avatar moves their head and you move yours, they do so as well.
- Heat map: A representation of activity within an area by means of color coding (e.g., red being high intensity). Used frequently in video games for telling players where large numbers of enemies are concentrated; also found in other contexts like mapping social media content to show levels of popularity throughout different regions worldwide based on what is shared most often from those locations.
- HUD Head-up display: Refers to any device that can be worn or mounted on one’s body that presents information to the user without obstructing their view.
- Immersion: The sensation of being in a virtual environment and believing what one sees is actually happening on some level (e.g., because it looks so real). It can sometimes be described as feeling like you’re there, or not noticing that you are still wearing your VR headset.
- Inside-out tracking: Refers to any form of motion capture where sensors within an HMD monitor movements; this may happen through camera movement tracking with cameras attached directly to the headgear itself, gyroscopes embedded into the device based on how much someone moves relative to when they last calibrated them for use, or other technologies such as accelerometers which measure acceleration and rotation.
- Latency: Refers to any delay in response time, which is what happens when you’re using your computer or another device and there’s a lag for the cursor on-screen to catch up with where you’ve moved it. It can be caused by interference from WiFi frequencies, as well as other physical obstructions like heavy snowstorms that keep electricity from reaching power lines so they turn off temporarily; latency also depends on how far away someone is located geographically speaking (e.g., if they are halfway around the world then data will take longer to get transmitted back and forth). Latency has an impact on virtual reality experiences because of its reliance on fast frame rates per second – video games may show some level of “lag” when a player moves their head and it takes time for the system to catch up with them.
- Locomotion: Refers to how people move through environments in virtual reality, which can be accomplished by walking around within an actual room or area that is mapped out electronically like Google’s Tilt Brush (see below) but also using devices such as omnidirectional treadmills and motion capture suits; this allows one to walk in any direction they want while still being able to feel immersed because of total body tracking.
- Mixed Reality: A blending between digital information and the real world from some form of augmented reality technology overlaid on top of what someone sees through video goggles or other HMDs — this includes both holographic projections and also semi-transparent screens that can be seen from the outside. Mixed reality has become a popular area for development in virtual environments because it is not as expensive as building an entirely new world with photorealistic graphics, which would require more processing power and other resources to do so accurately; instead, mixed reality allows developers to draw on their existing skillsets of coding or drawing using various programs like Unity (see below) while still making use of advanced capabilities such as head tracking.
- Monoscopic Video: Refers to any video recording where only one eye’s worth of depth information is recorded at time (i.e., left eye if looking through right lens). This means there will be less detail than there would be with stereoscopic video, and it will also not have as clear of a sense of depth perception (i.e., things in the foreground may look farther away than they actually are).
- Outside-in tracking: Refers to any form of motion capture where sensors outside an HMD track movements; this can either happen through cameras on the headset itself that map out head movement or other devices such as gyroscopes embedded into the device based on how much someone moves relative to when they last calibrated them for use, which is usually accomplished by having users walk around their living room while wearing VR goggles. This type of motion capture technology does not require external sensors like those found in inside-out tracking systems because data from one’s body is mapped out through cameras and sensors on the headset.
- Parallax: Refers to how objects in a virtual reality environment are rendered at different distances from one another based on perspective, which can be accomplished by using graphics engines like Unity that create a sense of depth perception; parallax effects can also be found on websites with HTML-based WebGL content because web browsers now support it (see below).
- Positional Audio: A type of audio where sound plays back as if it were coming from specific directions in an environment – this includes both realistic simulations such as being able to hear birds chirping overhead or people chatting loudly behind you as well as artificial sounds such as gunshots or other blasts happening off screen. Positional audio can be accomplished with head tracking because it is used to create a sense of immersion, which means that the more one turns their head in an environment (i.e., looking around), the louder and clearer sounds will become from various directions; this makes it sound as if things are happening all around you even though they may not actually be there at all.
- POV point of view: Refers to filming video either through first-person perspective or third person; different types of POVs include overhead shots where someone looks down on what’s going on like God would do, then close up angles such as found in thrillers for suspenseful moments, and also situational perspectives – these are usually filmed from someone’s point of view as they walk around an environment as if someone is looking at what they’re seeing through their eyes instead.
- Resolution: Refers to the resolution a video or image can be rendered in for any given headset, which includes less detailed images being provided with lower resolutions and clearer graphics being available with higher ones; however, this does not account for differences when it comes to pixel density because one cannot see the individual pixels unless viewing on something like a high-definition television that has a screen size anywhere from 47 inches to 86 inches (which would require 720p). Presently there are few headsets capable of delivering resolutions greater than 1080p such as those made by HTC Vive Pro (1440p), Oculus Rift (1440×1600) and Sony Playstation VR (1920×1080).
- Reticle: A type of computer interface that can be used to display or interact with various items in a virtual world, which is typically seen as crosshairs on top of one’s view; this could either be something like an actual dot inside the center circle for aiming purposes or it may also include other features such as showing levels of heat rising from objects in a video game.
- Side-by-side SBS: Refers to how videos are displayed when they’re stretched out so that two people side by side looking at each other will see themselves mirrored; if someone has their left eye on the screen then BOTH eyes should see themselves, but in the opposite way. This means that someone’s left eye is also on their right side of the screen and vice versa – this is how it looks to see yourself with two eyes looking at you head-on from another person’s perspective.
- Spherical Video: A type of 360 degree video where one can view any direction they want when watching; spherical videos are typically filmed by using multiple cameras placed strategically around a scene so footage can be captured all around instead of just what would fit inside a circle made by panning around with just one camera (which will result in more than 180 degrees).
- Stereoscopic Video: Refers to an immersive experience that uses stereoscopy, which is either through films or other media made for a person to watch while wearing special glasses that will make it seem as if you’re watching things happen in front of your eyes; this can also be accomplished with just one video being filmed using two cameras, where footage from each camera is captured at different angles so when they are played back on the screen or viewed through VR headsets people see depth. This is what gives an experience like virtual reality its realism since there’s more than meets the eye (literally); however, some stereoscopic videos are specifically designed only for 360 degree viewing which means those without any kind of headset or device cannot enjoy them because they’ll need something called “cross-eyed view” – wherein both images would have to be displayed side by side and then someone would need to close one of their eyes so they can view the image better. Showing a video in this way is also known as “fist-time” viewing or “cross-eyed”.
- Stitching Video: A type of 360 degree video where footage from multiple cameras are then stitched together using computer software that allows people to watch them on any device (including mobile) without needing anything more than just what’s available with an internet browser; some stitching videos may include additional features such as animations, sounds, and other things like graphics overlaid onto live feeds which help make for a more interactive experience.
- Tethered headset / Mobile Headset: Refers to how headsets work by either being connected via wire directly into something like a computer or gaming console (where it’s then plugged into the wall for power) OR via Bluetooth to something like an app on your phone.
- VR sickness: Refers to how some people might experience motion sickness due solely to Virtual Reality since VR doesn’t allow you any sense of control over what happens once you put on the headset – so even just looking around without turning means movement because there’s no barrier between you and the virtual world.
- WebGL: A web standard that’s used by developers to create interactive graphics; it can work both with browser-based games as well as VR applications (depending on what kind of headset someone might be using).
- WebVR: WebGL for Virtual Reality, which is a relatively new technology but one that will continue to become more important in how people interact with each other online.