Citizens Band radio, often abbreviated as CB radio, is a system of short-distance radio communications. It allows individuals to communicate over specific frequencies without the need for a license. CB radios are commonly used by truck drivers, hobbyists, and in emergency situations, providing a simple way to share information and coordinate activities. CB radios operate on 40 channels within the 27 MHz band. Users can transmit voice messages, and some models also support data transmission. The range of communication typically varies from a few miles to several dozen miles, depending on the terrain and equipment used.