Ubiquitous computing refers to a paradigm shift in which computing systems become seamlessly integrated into everyday life, rendering their impact on individuals, institutions, and societies nearly invisible. In a world governed by ubiquitous computing, these systems progressively blur the boundaries between the physical and digital realms, operating continuously and imperceptibly. This study explores the fundamental concepts, historical evolution, and key components of ubiquitous computing, while also examining how emerging technologies such as smart environments, the Internet of Things and artificial intelligence are utilized within this framework. Furthermore, the study evaluates the applications of these technologies at both individual and societal levels, discusses the increasing significance of ethical and privacy concerns, and presents insights into potential future trends in the field.