Wireless communication is the fastest-growing field in the telecommunication industry. Wireless networks have grown significantly as an important segment of the communications industry. They have become popular networks with the potential to provide high-speed, high-quality information exchange between two or more portable devices without any wire or conductors. Wireless networks can simply be characterized as the technology that provides seamless access to information, anywhere, anyplace, and anytime without being wired. This emerging technology builds on existing technologies such as radio engineering, data communications, computer networks, distributed systems, information management, and applications. The technology is based on radio and infrared transmission mechanisms and uses technologies such as cellular telephony, personal communications systems, wireless private branch exchanges, and wireless local area networks. The wireless radio network system facilitates mobility in communication. Systems achieve mobility by transmitting data via radio waves over the air. In a wireless network, the signal has no wire on which to travel in any particular direction, whereas in wired networks, signals only travel along the wire. In addition, the benefits of wireless networking include things such as increased mobility, simple and flexible installation, and easy scalability. Applications of this emerging technology are many, which range from the multimedia internet-enabled cell phones to smart homes and appliances to automated highway systems, video teleconferencing and distance learning, and autonomous sensor networks. This article discusses the history, present state, and future of wireless networks. It also describes the fundamentals of wireless communication and explains the basic concepts at a level accessible to an audience with a basic background in digital communication. Wiley Online library