# Extended Reality: Types and Applications
## 3 Applications of Extended Reality
### Extended Reality and Its Usage
#### 3.1.2 Augmented Reality and Its Usage
(**c**) Reducing maintenance error with AR glasses. (**d**) HMD AR-supported collaborative repair operations of industrial robots. (**e**) Adaptive AR instructions for complex industrial operations. (**f**) AR-assisted deep learning-based approach for automatic inspection. (**g**) HMD AR-based humanentric approach for maintenance. (**h**) AR in intralogistics. Figure 5: Example of AR-assisted visualization of guidance information for machine maintenance [50]. (**a**) Overlay of virtual information on the actual equipment bay; (**b**) bolt holes to be assembled are highlighted in yellow; (**c**) bolt holes that are occluded are highlighted in yellow; (**d**) the occluded area can be seen through the virtual model. Data Display--Head-up displays are also an element of augmented reality. This method of visualization is often found in modern fighters to display information about the combat situation, targets, targeting systems, radars, and parameters of internal systems [51]. Some models of cars are equipped with a head-up display from the factory, which projects information onto the windshield or a transparent reflector screen to indicate the speed of the car, the direction of movement according to navigation, data on multimedia, phone calls, and various notifications. This allows you to move your gaze minimally, without losing sight of the traffic situation, making driving safer and more comfortable [52]. Holographic displays are sometimes used in advertising, allowing you not only to display an image but to superimpose it on an object standing behind the screen, thereby supplementing it with effects or a description and attracting the attention of potential buyers with an unusual appearance [53]. * Architecture and Design--In architecture, AR is used to visualize structures, arrange furniture, and design based on a real room. This allows engineers and designers to clearly show the customer or designer how the construction process will look at different stages or the final result, namely to evaluate the project before construction begins [54]. This method allows the customer to better understand the project and avoid alterations at the construction stage. An interesting solution was presented in an article [55] where the researchers used a mobile robot that navigates in space and has a built-in projector that projects the necessary drawings from a 3D BIM model in real scale onto the wall. The system automatically adjusts the image to the surface, even a curved one, regardless of where the robot with the projector is placed. It can show the electrical wiring diagram; the location of pipes for water and sewage; and the heating, air conditioning, and ventilation systems. This system allows information to be visualized without the need to wear or hold the device. Furthermore, information can be seen by several people simultaneously. For workers, the use of AR helps them navigate large spaces and check tasks that need to be completed in a specific area to avoid errors and improve the use of time and resources. It also offers the ability to watch the construction work process remotely [56]. In conclusion, augmented reality is an excellent method of visualizing virtual objects in the real world, which is used in a lot of applications such as architecture, navigation, tourism, education, medicine, assistance, and production. AR also helps in assisting, which simplifies and accelerates the understanding of tasks, learning, experimenting, and conducting simulations interactively.