This chapter provides a comprehensive overview of sensors in medical technology, enlisting their applications in orthopaedics. It defines sensors, explores their components and functions, and discusses various types of sensors used in healthcare. The chapter compares analogue and digital sensors, highlighting their advantages and disadvantages. It also addresses current challenges faced by sensors in medical applications and explores promising future directions, such as advancements in materials, miniaturization, energy efficiency, AI integration, and biocompatibility. Furthermore, the chapter examines the role of sensors in the Internet of Things (IoT), emphasizing their contributions to data collection, communication, automation, analytics, and safety. Overall, this chapter offers a valuable resource for medical professionals, particularly orthopaedic surgeons, seeking to understand the significance and potential of sensor technology in improving patient care and outcomes.