5 GHz is a range of radio frequencies used by Wi-Fi and other wireless systems. Compared with 2.4 GHz, it can provide higher data rates and encounter less congestion in some settings, but its signals generally have shorter range and pass through walls less effectively. Actual performance depends on equipment, channel use, antenna design, and local conditions.
In cyber security, 5 GHz is relevant whenever devices exchange data over the air, including a video link between a drone and its receiver. Defenders can monitor radio activity and review device firmware and configuration to understand what a system is transmitting; the frequency alone does not establish that a transmission is unsafe or unauthorized. Wireless links should also use appropriate authentication and encryption, since choosing a frequency band does not secure the data.