What does "modulation" refer to in communications?

Modulation in communications refers specifically to the process of varying a carrier signal’s properties to convey information. This involves changing aspects such as the amplitude, frequency, or phase of the carrier wave, allowing it to carry data over various communication mediums. The primary purpose of modulation is to transmit information effectively over distances, enabling it to be decoded correctly by the receiving end.

When modulation occurs, the original signal, which may be audio or data, is encoded into a format suitable for transmission. This process allows signals to be sent over airwaves or through cables efficiently, reducing issues such as interference and bandwidth limitations. Through modulation, systems can adapt to different transmission environments and requirements, ensuring robust communication.