The Semantic Web is a vision of the web where information is given well-defined meaning, enabling machines and humans to work more collaboratively. This paper gives a comprehensive review of the architecture, key concepts, and practical applications of the Semantic Web, with special focus on its implementation in the travel domain. The goal is to explore how Semantic Web technologies such as RDF, OWL, and SPARQL can be used to augment data interoperability, facilitate context-aware recommendations, and improve the user experience within travel-related services. It analyzes key concepts such as ontologies, linked data, and semantic annotations illustrating their role in structuring information about travel while enabling intelligent applications such as itinerary planning and cross-domain recommendation. The scope of the review covers applications in practice by sectors such as healthcare, e-commerce, and travel, giving an idea about how the Semantic Web is actually changing the method of data integration and decision-making. The purpose of this paper is to give an overview of the overall architecture of the Semantic. We explore how foundational technologies like URIs, RDF, and OWL play their roles in creating a semantic layer on top of the existing web, allowing interoperable and machine-readable data structures. Core concepts include ontologies, linked data, and reasoning mechanisms.