This chapter investigates the convergence of the Internet of Things (IoT) and big data analytics, focusing on how the integration of these two domains can unlock transformative value across a wide range of applications. With the exponential growth of IoT devices—including sensors, mobile terminals, vehicles, and edge systems—the volume, velocity, and variety of data generated in real time have escalated to unprecedented levels. This surge in data poses significant challenges for data storage, processing, and analysis. The chapter first outlines the conceptual relationship between IoT and big data, emphasizing how analytics technologies are essential for extracting actionable insights from continuous data streams. It then reviews representative architectures, platforms, and current research efforts that facilitate data-driven decision-making in IoT ecosystems. Key application scenarios are discussed, including predictive maintenance, environmental monitoring, and smart city infrastructure. Finally, the chapter highlights major open challenges such as scalability, security, data heterogeneity, and real-time processing, offering perspectives on future directions in building integrated and intelligent IoT-big data frameworks.