With the emergence of the Internet of things (IoT) and machine-to-machine (M2M) communications, massive growth in the sensor node deployment is expected soon. According to IHS Markit forecast, the number of connected IoT devices would grow to 125 billion by 2030. The exponential growth in IoT is impacting virtually all stages of industry and nearly all market areas. It is redefining the ways to design, manage, and maintain the networks, data, clouds, and connections. To support the requirements of new applications, an innovative paradigm called low-power wide-area networks (LPWAN) is evolved. The LPWAN is a class of wireless IoT communication standards and solutions with characteristics such as large coverage areas, low transmission data rates with small packet data sizes, and long battery life operation. The LPWAN technologies are being deployed and have shown enormous potential for the vast range of applications in IoT and M2M, especially in constrained environments. This chapter focuses on a general introduction to LPWANs, innovative applications and services, requirements, wireless access, and characteristics. © 2020 Elsevier Inc. All rights reserved.