Augmented reality, commonly abbreviated "AR," is computer-generated content overlaid on a real world environment. AR hardware comes in many forms, including devices that you can carry, such as handheld displays, and devices you wear, such as headsets, and glasses. Common applications of AR technology include video games, television, and personal navigation, though there are many other uses as well.
Pokémon Go is a popular video game that uses augmented reality. The app, which runs on iOS and Android devices, uses your smartphone's GPS signal to detect your location. As you walk around, your avatar is overlaid on a real-world map, along with in-game content, such as Pokéstops, gyms, and Pokemon that appear. When you attempt to catch a Pokémon, it shows up with a real-word background created by your smartphone's camera. The camera can be turned on or off using the "AR" toggle switch.
Augmented reality is also used in television, especially in sports. For example, golf broadcasts sometimes display a line on the screen that tracks the flight of the ball. NFL games display a first down line overlaid on the field. Major league baseball games often display dynamically generated ads behind home plate. In olympic races, a world record (WR) line is displayed during some races to show how close an athlete is to a record time.
In navigation, AR is used to display location information in real-time. This is typically done through a heads-up display (HUD) that projects images in front of you like a hologram. For instance, HUD in an automobile might display your speed, engine RPMs, and other useful data. Google Glass, a head-mounted display, can overlay directions from Google Maps and identify locations using the built-in camera.
AR vs VR
While augmented reality and virtual reality share some things in common, they are two different technologies. AR augments reality, but doesn't replace it. VR completely replaces your surroundings with a virtual environment. Therefore, any hardware that combines digital content with your actual surroundings is an AR device. Hardware that operates independently from your location and encompasses your vision is a VR device.