## 2 Background  
### Industry 4.0 Background  
To understand Industry 4.0, it is essential to analyze the evolution of the Industrial Revolutions, which arose in response to increasing industrial demands and the quest for greater productivity [1; 12]. Thus, significant industrial and technological revolutions have occurred with the emergence of new technologies and production methods [44], marked by technical innovations aimed at improving the efficiency of production systems [45], as can be seen in Figure 1.  
The first industrial revolution emerged in Great Britain in the late 18 th and early 19 th centuries, around 1760. It was marked by the rise of mechanical production, driven by hydraulic power and the steam engine. This period represented a significant transformation, transitioning from an agrarian and artisanal economy to a manufacturing system that utilized machines in the production process [3; 4; 44; 46]. Additionally, the first industrial revolution had significant social, environmental, and economic impacts, such as the emergence of new community life centers, advancements in industrialization, and the rise of new working classes [12]. The second industrial revolution began around the 1900s, in the late 19 th century [4]. This phase marked the beginning of mass production, which used electric power and was characterized by assembly-line production based on division of labor [3; 5; 44]. During this period, there was also an intensification in the use of oil, which became a major driver of the second industrial revolution [4]. Because of this second revolution, [12] highlights a significant increase in the population migrating to large urban centers and a transformation in communication with the emergence of radio and telephone (made possible by the widespread use of electricity). The third industrial revolution occurred in the mid-20 th century and was characterized by the use of electronic systems and information technology (IT) and the promotion of automated production, which resulted in the emergence of computers and smartphones, as well as the use of cloud computing and automation. Consequently, however, there was a high level of unemployment, global warming, financial crises, and other challenges [4; 5; 12; 44; 46]. Finally, the fourth industrial revolution is currently taking place and is characterized by the use of cyber-physical systems (CPS), which have led to significant changes in the industry [3]. Ref. [47] emphasizes that this revolution also marks the use of artificial intelligence, cloud computing, nanotechnology, and biotechnologies, among other technological advancements. Although the fourth industrial revolution is focused on the concepts of digital manufacturing, its scope is much broader, involving the integration of digital systems and the digitization of assets throughout the entire value chain [48]. Consequently, [1] emphasizes that the fourth industrial revolution presents distinct characteristics regarding scope, size, and complexity and, therefore, should be discussed and understood separately. The concept of Industry 4.0, according to [10], is associated with large-scale changes involving the digitization of all types of processes, products, and services, directly affecting almost all areas involving the production system. Thus, Industry 4.0 can be defined as a process that connects machines, people, and products with digital technologies [49; 50]. The term Industry 4.0 originated during the Hightech Strategy for 2020, which took place in Germany in November 2011 and has since become a focus of study worldwide. This term is part of a set of government initiatives in German-speaking countries to become  
Figure 1: History of Industrial Revolutions. leaders in integrated industry. In 2012, a group was formed to popularize the term Industry 4.0 as the fourth industrial revolution. In 2013, the same group presented a final report on Industry 4.0 at the Hannover Messe [3; 24; 35; 51; 52; 53].