Transmission power refers to the amount of energy used to send signals over a communication medium, such as radio waves or fiber optics. It is measured in watts and determines how far and effectively a signal can travel. Higher transmission power can improve signal strength and coverage, but it may also lead to increased interference and energy consumption. In wireless communication, devices like cell phones and Wi-Fi routers rely on optimal transmission power to maintain clear connections. Regulatory bodies often set limits on transmission power to minimize interference between different devices and ensure efficient use of the available spectrum.