The Internet of Things (IoT) for smart buildings is a growing research area focused on creating intelligent, energy-efficient, and automated building environments through interconnected devices, sensors, and control systems. Research papers in this domain explore applications such as HVAC optimization, lighting control, occupancy monitoring, energy management, security and surveillance, and predictive maintenance. Key contributions include AI-driven analytics, edge/fog computing for real-time decision-making, interoperability frameworks for heterogeneous devices, and secure, privacy-preserving data management. Recent studies also address challenges like scalability, reliability, cybersecurity, and integration with smart grids and building management systems (BMS). By combining IoT technologies with advanced automation and predictive modeling, smart building research aims to enhance comfort, safety, operational efficiency, and sustainability in modern built environments.