---

This article examines the concept of digital twin as key element of industry 4.0, based on data analytics and IoT (internet of things).
The authors also pays attention to the differences between the concepts of the digital twin, digital model, and digital shadow, and track their evolution as the technology develops. This contributes a more precise understanding of the interaction between physical and virtual systems.

Further in article describes the main application areas of the digital twins technology, such as production, healthcare and smart cities. The most widespread usage and implementation of digital twins has been in the field of industry production. There this technology helps with a monitoring, managing, forecasting and optimizing processes. The authors provide examples of existing projects where used a digital twin technology.

In this part of the article, also discussed the key challenges and issues related to the development and implementation of Digital Twin, including limitations of IT infrastructure and issues of data security and privacy, as well as the need for additional equipment deployment. The authors highlight the importance of resolving this issues for the further development of the Digital twin technology.