This document discusses wireless communication and different wireless technologies. It begins by explaining the benefits of wireless communication such as freedom from wires and global coverage. It then defines wireless communication as transmitting voice and data using electromagnetic waves without a physical connection. The document outlines common frequency bands used in wireless communication and describes how communication takes place using transmitting and receiving antennas. It discusses different types of wireless transmission technologies including radio, microwave, infrared, light waves and their advantages and disadvantages. Finally, it provides overviews of common wireless systems such as cellular networks, wireless LANs, satellite systems, paging systems and personal area networks like Bluetooth.